.NET Framework Class Library
IDictionaryTKey, TValue Interface

Represents a generic collection of key/value pairs.

Namespace:   System.Collections.Generic
Assembly:  mscorlib (in mscorlib.dll)
Syntax
Public Interface IDictionary(Of TKey, TValue) _
	Inherits [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_0_0_0%](Of [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_0_0_1%](Of TKey, TValue)),  _
	[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_0_0_2%](Of [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_0_0_3%](Of TKey, TValue)), [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_0_0_4%]
public interface IDictionary<TKey, TValue> : [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_1_0_0%]<[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_1_0_1%]<TKey, TValue>>, 
	[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_1_0_2%]<[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_1_0_3%]<TKey, TValue>>, [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_1_0_4%]
generic<typename TKey, typename TValue>
public interface class IDictionary : [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_2_0_0%]<[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_2_0_1%]<TKey, TValue>>, 
	[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_2_0_2%]<[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_2_0_3%]<TKey, TValue>>, [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_2_0_4%]
type IDictionary<'TKey, 'TValue> =  
    interface 
        interface [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_3_0_0%]<[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_3_0_1%]<'TKey, 'TValue>>
        interface [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_3_0_2%]<[%$TOPIC/s4ys34ea_en-us_VS_110_1_0_3_0_3%]<'TKey, 'TValue>>
        interface [%$TOPIC/s4ys34ea_en-us_VS_110_1_0_3_0_4%] 
    end
JScript does not support generic types or methods.

Type Parameters

TKey

The type of keys in the dictionary.

TValue

The type of values in the dictionary.

The IDictionaryTKey, TValue type exposes the following members.

Properties
  NameDescription
Public property Supported by the XNA Framework Supported by Portable Class Library CountGets the number of elements contained in the ICollectionT. (Inherited from ICollectionT.)
Public property Supported by the XNA Framework Supported by Portable Class Library IsReadOnlyGets a value indicating whether the ICollectionT is read-only. (Inherited from ICollectionT.)
Public property Supported by the XNA Framework Supported by Portable Class Library ItemGets or sets the element with the specified key.
Public property Supported by the XNA Framework Supported by Portable Class Library KeysGets an ICollectionT containing the keys of the IDictionaryTKey, TValue.
Public property Supported by the XNA Framework Supported by Portable Class Library ValuesGets an ICollectionT containing the values in the IDictionaryTKey, TValue.
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Methods
  NameDescription
Public method Supported by the XNA Framework Supported by Portable Class Library Add(T)Adds an item to the ICollectionT. (Inherited from ICollectionT.)
Public method Supported by the XNA Framework Supported by Portable Class Library Add(TKey, TValue)Adds an element with the provided key and value to the IDictionaryTKey, TValue.
Public method Supported by the XNA Framework Supported by Portable Class Library ClearRemoves all items from the ICollectionT. (Inherited from ICollectionT.)
Public method Supported by the XNA Framework Supported by Portable Class Library ContainsDetermines whether the ICollectionT contains a specific value. (Inherited from ICollectionT.)
Public method Supported by the XNA Framework Supported by Portable Class Library ContainsKeyDetermines whether the IDictionaryTKey, TValue contains an element with the specified key.
Public method Supported by the XNA Framework Supported by Portable Class Library CopyToCopies the elements of the ICollectionT to an Array, starting at a particular Array index. (Inherited from ICollectionT.)
Public method Supported by the XNA Framework Supported by Portable Class Library GetEnumeratorReturns an enumerator that iterates through the collection. (Inherited from IEnumerableT.)
Public method Supported by the XNA Framework Supported by Portable Class Library Remove(T)Removes the first occurrence of a specific object from the ICollectionT. (Inherited from ICollectionT.)
Public method Supported by the XNA Framework Supported by Portable Class Library Remove(TKey)Removes the element with the specified key from the IDictionaryTKey, TValue.
Public method Supported by the XNA Framework Supported by Portable Class Library TryGetValueGets the value associated with the specified key.
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Extension Methods
  NameDescription
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AggregateKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, KeyValuePairTKey, TValue, KeyValuePairTKey, TValue)Overloaded. Applies an accumulator function over a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AggregateKeyValuePairTKey, TValue, TAccumulate(TAccumulate, FuncTAccumulate, KeyValuePairTKey, TValue, TAccumulate)Overloaded. Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AggregateKeyValuePairTKey, TValue, TAccumulate, TResult(TAccumulate, FuncTAccumulate, KeyValuePairTKey, TValue, TAccumulate, FuncTAccumulate, TResult)Overloaded. Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value, and the specified function is used to select the result value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AllKeyValuePairTKey, TValueDetermines whether all elements of a sequence satisfy a condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AnyKeyValuePairTKey, TValueOverloaded. Determines whether a sequence contains any elements. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AnyKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Determines whether any element of a sequence satisfies a condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AsEnumerableKeyValuePairTKey, TValueReturns the input typed as IEnumerableT. (Defined by Enumerable.)
Public Extension Method Supported by Portable Class Library AsParallelOverloaded. Enables parallelization of a query. (Defined by ParallelEnumerable.)
Public Extension Method Supported by Portable Class Library AsParallelKeyValuePairTKey, TValueOverloaded. Enables parallelization of a query. (Defined by ParallelEnumerable.)
Public Extension Method Supported by Portable Class Library AsQueryableOverloaded. Converts an IEnumerable to an IQueryable. (Defined by Queryable.)
Public Extension Method Supported by Portable Class Library AsQueryableKeyValuePairTKey, TValueOverloaded. Converts a generic IEnumerableT to a generic IQueryableT. (Defined by Queryable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDecimal)Overloaded. Computes the average of a sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDouble)Overloaded. Computes the average of a sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32)Overloaded. Computes the average of a sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt32)Overloaded. Computes the average of a sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int64)Overloaded. Computes the average of a sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt64)Overloaded. Computes the average of a sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Single)Overloaded. Computes the average of a sequence of Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableSingle)Overloaded. Computes the average of a sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Double)Overloaded. Computes the average of a sequence of Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library AverageKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Decimal)Overloaded. Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library CastTResultCasts the elements of an IEnumerable to the specified type. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ConcatKeyValuePairTKey, TValueConcatenates two sequences. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ContainsKeyValuePairTKey, TValue(KeyValuePairTKey, TValue)Overloaded. Determines whether a sequence contains a specified element by using the default equality comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ContainsKeyValuePairTKey, TValue(KeyValuePairTKey, TValue, IEqualityComparerKeyValuePairTKey, TValue)Overloaded. Determines whether a sequence contains a specified element by using a specified IEqualityComparerT. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library CountKeyValuePairTKey, TValueOverloaded. Returns the number of elements in a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library CountKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns a number that represents how many elements in the specified sequence satisfy a condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library DefaultIfEmptyKeyValuePairTKey, TValueOverloaded. Returns the elements of the specified sequence or the type parameter's default value in a singleton collection if the sequence is empty. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library DefaultIfEmptyKeyValuePairTKey, TValue(KeyValuePairTKey, TValue)Overloaded. Returns the elements of the specified sequence or the specified value in a singleton collection if the sequence is empty. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library DistinctKeyValuePairTKey, TValueOverloaded. Returns distinct elements from a sequence by using the default equality comparer to compare values. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library DistinctKeyValuePairTKey, TValue(IEqualityComparerKeyValuePairTKey, TValue)Overloaded. Returns distinct elements from a sequence by using a specified IEqualityComparerT to compare values. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ElementAtKeyValuePairTKey, TValueReturns the element at a specified index in a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ElementAtOrDefaultKeyValuePairTKey, TValueReturns the element at a specified index in a sequence or a default value if the index is out of range. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ExceptKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue)Overloaded. Produces the set difference of two sequences by using the default equality comparer to compare values. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ExceptKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue, IEqualityComparerKeyValuePairTKey, TValue)Overloaded. Produces the set difference of two sequences by using the specified IEqualityComparerT to compare values. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library FirstKeyValuePairTKey, TValueOverloaded. Returns the first element of a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library FirstKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns the first element in a sequence that satisfies a specified condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library FirstOrDefaultKeyValuePairTKey, TValueOverloaded. Returns the first element of a sequence, or a default value if the sequence contains no elements. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library FirstOrDefaultKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns the first element of the sequence that satisfies a condition or a default value if no such element is found. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey)Overloaded. Groups the elements of a sequence according to a specified key selector function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey, IEqualityComparerTKey)Overloaded. Groups the elements of a sequence according to a specified key selector function and compares the keys by using a specified comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey, TElement(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement)Overloaded. Groups the elements of a sequence according to a specified key selector function and projects the elements for each group by using a specified function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey, TResult(FuncKeyValuePairTKey, TValue, TKey, FuncTKey, IEnumerableKeyValuePairTKey, TValue, TResult)Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey, TElement(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement, IEqualityComparerTKey)Overloaded. Groups the elements of a sequence according to a key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey, TResult(FuncKeyValuePairTKey, TValue, TKey, FuncTKey, IEnumerableKeyValuePairTKey, TValue, TResult, IEqualityComparerTKey)Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The keys are compared by using a specified comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey, TElement, TResult(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement, FuncTKey, IEnumerableTElement, TResult)Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupByKeyValuePairTKey, TValue, TKey, TElement, TResult(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement, FuncTKey, IEnumerableTElement, TResult, IEqualityComparerTKey)Overloaded. Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupJoinKeyValuePairTKey, TValue, TInner, TKey, TResult(IEnumerableTInner, FuncKeyValuePairTKey, TValue, TKey, FuncTInner, TKey, FuncKeyValuePairTKey, TValue, IEnumerableTInner, TResult)Overloaded. Correlates the elements of two sequences based on equality of keys and groups the results. The default equality comparer is used to compare keys. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library GroupJoinKeyValuePairTKey, TValue, TInner, TKey, TResult(IEnumerableTInner, FuncKeyValuePairTKey, TValue, TKey, FuncTInner, TKey, FuncKeyValuePairTKey, TValue, IEnumerableTInner, TResult, IEqualityComparerTKey)Overloaded. Correlates the elements of two sequences based on key equality and groups the results. A specified IEqualityComparerT is used to compare keys. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library IntersectKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue)Overloaded. Produces the set intersection of two sequences by using the default equality comparer to compare values. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library IntersectKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue, IEqualityComparerKeyValuePairTKey, TValue)Overloaded. Produces the set intersection of two sequences by using the specified IEqualityComparerT to compare values. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library JoinKeyValuePairTKey, TValue, TInner, TKey, TResult(IEnumerableTInner, FuncKeyValuePairTKey, TValue, TKey, FuncTInner, TKey, FuncKeyValuePairTKey, TValue, TInner, TResult)Overloaded. Correlates the elements of two sequences based on matching keys. The default equality comparer is used to compare keys. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library JoinKeyValuePairTKey, TValue, TInner, TKey, TResult(IEnumerableTInner, FuncKeyValuePairTKey, TValue, TKey, FuncTInner, TKey, FuncKeyValuePairTKey, TValue, TInner, TResult, IEqualityComparerTKey)Overloaded. Correlates the elements of two sequences based on matching keys. A specified IEqualityComparerT is used to compare keys. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library LastKeyValuePairTKey, TValueOverloaded. Returns the last element of a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library LastKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns the last element of a sequence that satisfies a specified condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library LastOrDefaultKeyValuePairTKey, TValueOverloaded. Returns the last element of a sequence, or a default value if the sequence contains no elements. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library LastOrDefaultKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns the last element of a sequence that satisfies a condition or a default value if no such element is found. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library LongCountKeyValuePairTKey, TValueOverloaded. Returns an Int64 that represents the total number of elements in a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library LongCountKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns an Int64 that represents how many elements in a sequence satisfy a condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValueOverloaded. Returns the maximum value in a generic sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDecimal)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Decimal value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDouble)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Double value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Int32 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt32)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Int32 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int64)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Int64 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt64)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Int64 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Single)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Single value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableSingle)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Single value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Double)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Double value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Decimal)Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Decimal value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MaxKeyValuePairTKey, TValue, TResult(FuncKeyValuePairTKey, TValue, TResult)Overloaded. Invokes a transform function on each element of a generic sequence and returns the maximum resulting value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValueOverloaded. Returns the minimum value in a generic sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDecimal)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Decimal value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDouble)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Double value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Int32 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt32)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Int32 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int64)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Int64 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt64)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Int64 value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Single)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Single value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableSingle)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Single value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Double)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Double value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Decimal)Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Decimal value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library MinKeyValuePairTKey, TValue, TResult(FuncKeyValuePairTKey, TValue, TResult)Overloaded. Invokes a transform function on each element of a generic sequence and returns the minimum resulting value. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library OfTypeTResultFilters the elements of an IEnumerable based on a specified type. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library OrderByKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey)Overloaded. Sorts the elements of a sequence in ascending order according to a key. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library OrderByKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey, IComparerTKey)Overloaded. Sorts the elements of a sequence in ascending order by using a specified comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library OrderByDescendingKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey)Overloaded. Sorts the elements of a sequence in descending order according to a key. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library OrderByDescendingKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey, IComparerTKey)Overloaded. Sorts the elements of a sequence in descending order by using a specified comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ReverseKeyValuePairTKey, TValueInverts the order of the elements in a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SelectKeyValuePairTKey, TValue, TResult(FuncKeyValuePairTKey, TValue, TResult)Overloaded. Projects each element of a sequence into a new form. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SelectKeyValuePairTKey, TValue, TResult(FuncKeyValuePairTKey, TValue, Int32, TResult)Overloaded. Projects each element of a sequence into a new form by incorporating the element's index. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SelectManyKeyValuePairTKey, TValue, TResult(FuncKeyValuePairTKey, TValue, IEnumerableTResult)Overloaded. Projects each element of a sequence to an IEnumerableT and flattens the resulting sequences into one sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SelectManyKeyValuePairTKey, TValue, TResult(FuncKeyValuePairTKey, TValue, Int32, IEnumerableTResult)Overloaded. Projects each element of a sequence to an IEnumerableT, and flattens the resulting sequences into one sequence. The index of each source element is used in the projected form of that element. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SelectManyKeyValuePairTKey, TValue, TCollection, TResult(FuncKeyValuePairTKey, TValue, Int32, IEnumerableTCollection, FuncKeyValuePairTKey, TValue, TCollection, TResult)Overloaded. Projects each element of a sequence to an IEnumerableT, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. The index of each source element is used in the intermediate projected form of that element. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SelectManyKeyValuePairTKey, TValue, TCollection, TResult(FuncKeyValuePairTKey, TValue, IEnumerableTCollection, FuncKeyValuePairTKey, TValue, TCollection, TResult)Overloaded. Projects each element of a sequence to an IEnumerableT, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SequenceEqualKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue)Overloaded. Determines whether two sequences are equal by comparing the elements by using the default equality comparer for their type. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SequenceEqualKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue, IEqualityComparerKeyValuePairTKey, TValue)Overloaded. Determines whether two sequences are equal by comparing their elements by using a specified IEqualityComparerT. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SingleKeyValuePairTKey, TValueOverloaded. Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SingleKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SingleOrDefaultKeyValuePairTKey, TValueOverloaded. Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SingleOrDefaultKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns the only element of a sequence that satisfies a specified condition or a default value if no such element exists; this method throws an exception if more than one element satisfies the condition. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SkipKeyValuePairTKey, TValueBypasses a specified number of elements in a sequence and then returns the remaining elements. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SkipWhileKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SkipWhileKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32, Boolean)Overloaded. Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements. The element's index is used in the logic of the predicate function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDecimal)Overloaded. Computes the sum of the sequence of nullable Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableDouble)Overloaded. Computes the sum of the sequence of nullable Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32)Overloaded. Computes the sum of the sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt32)Overloaded. Computes the sum of the sequence of nullable Int32 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int64)Overloaded. Computes the sum of the sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableInt64)Overloaded. Computes the sum of the sequence of nullable Int64 values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Single)Overloaded. Computes the sum of the sequence of Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, NullableSingle)Overloaded. Computes the sum of the sequence of nullable Single values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Double)Overloaded. Computes the sum of the sequence of Double values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library SumKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Decimal)Overloaded. Computes the sum of the sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library TakeKeyValuePairTKey, TValueReturns a specified number of contiguous elements from the start of a sequence. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library TakeWhileKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Returns elements from a sequence as long as a specified condition is true. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library TakeWhileKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32, Boolean)Overloaded. Returns elements from a sequence as long as a specified condition is true. The element's index is used in the logic of the predicate function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToArrayKeyValuePairTKey, TValueCreates an array from a IEnumerableT. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToDictionaryKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey)Overloaded. Creates a DictionaryTKey, TValue from an IEnumerableT according to a specified key selector function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToDictionaryKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey, IEqualityComparerTKey)Overloaded. Creates a DictionaryTKey, TValue from an IEnumerableT according to a specified key selector function and key comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToDictionaryKeyValuePairTKey, TValue, TKey, TElement(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement)Overloaded. Creates a DictionaryTKey, TValue from an IEnumerableT according to specified key selector and element selector functions. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToDictionaryKeyValuePairTKey, TValue, TKey, TElement(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement, IEqualityComparerTKey)Overloaded. Creates a DictionaryTKey, TValue from an IEnumerableT according to a specified key selector function, a comparer, and an element selector function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToListKeyValuePairTKey, TValueCreates a ListT from an IEnumerableT. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToLookupKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey)Overloaded. Creates a LookupTKey, TElement from an IEnumerableT according to a specified key selector function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToLookupKeyValuePairTKey, TValue, TKey(FuncKeyValuePairTKey, TValue, TKey, IEqualityComparerTKey)Overloaded. Creates a LookupTKey, TElement from an IEnumerableT according to a specified key selector function and key comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToLookupKeyValuePairTKey, TValue, TKey, TElement(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement)Overloaded. Creates a LookupTKey, TElement from an IEnumerableT according to specified key selector and element selector functions. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library ToLookupKeyValuePairTKey, TValue, TKey, TElement(FuncKeyValuePairTKey, TValue, TKey, FuncKeyValuePairTKey, TValue, TElement, IEqualityComparerTKey)Overloaded. Creates a LookupTKey, TElement from an IEnumerableT according to a specified key selector function, a comparer and an element selector function. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library UnionKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue)Overloaded. Produces the set union of two sequences by using the default equality comparer. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library UnionKeyValuePairTKey, TValue(IEnumerableKeyValuePairTKey, TValue, IEqualityComparerKeyValuePairTKey, TValue)Overloaded. Produces the set union of two sequences by using a specified IEqualityComparerT. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library WhereKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Boolean)Overloaded. Filters a sequence of values based on a predicate. (Defined by Enumerable.)
Public Extension Method Supported by the XNA Framework Supported by Portable Class Library WhereKeyValuePairTKey, TValue(FuncKeyValuePairTKey, TValue, Int32, Boolean)Overloaded. Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function. (Defined by Enumerable.)
Public Extension Method Supported by Portable Class Library ZipKeyValuePairTKey, TValue, TSecond, TResultApplies a specified function to the corresponding elements of two sequences, producing a sequence of the results. (Defined by Enumerable.)
Top
Remarks

The IDictionaryTKey, TValue interface is the base interface for generic collections of key/value pairs.

Each element is a key/value pair stored in a KeyValuePairTKey, TValue object.

Each pair must have a unique key. Implementations can vary in whether they allow key to be . The value can be and does not have to be unique. The IDictionaryTKey, TValue interface allows the contained keys and values to be enumerated, but it does not imply any particular sort order.

The foreach statement of the C# language (For Each in Visual Basic, for each in C++) returns an object of the type of the elements in the collection. Since each element of the IDictionaryTKey, TValue is a key/value pair, the element type is not the type of the key or the type of the value. Instead, the element type is KeyValuePairTKey, TValue. For example:

For Each kvp As KeyValuePair(Of Integer, String) In myDictionary
    Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value)
Next kvp
foreach (KeyValuePair<int, string> kvp in myDictionary)
{
    Console.WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
}
for each(KeyValuePair<int, String^> kvp in myDictionary)
{
    Console::WriteLine("Key = {0}, Value = {1}", kvp.Key, kvp.Value);
}

The foreach statement is a wrapper around the enumerator, which only allows reading from, not writing to, the collection.

NoteNote

Because keys can be inherited and their behavior changed, their absolute uniqueness cannot be guaranteed by comparisons using the Equals method.

Notes to Implementers

The implementing class must have a means to compare keys.

Examples

The following code example creates an empty DictionaryTKey, TValue of strings, with integer keys, and accesses it through the IDictionaryTKey, TValue interface.

The code example uses the Add method to add some elements. The example demonstrates that the Add method throws ArgumentException when attempting to add a duplicate key.

The example uses the Item property (the indexer in C#) to retrieve values, demonstrating that a KeyNotFoundException is thrown when a requested key is not present, and showing that the value associated with a key can be replaced.

The example shows how to use the TryGetValue method as a more efficient way to retrieve values if a program often must try key values that are not in the dictionary, and how to use the ContainsKey method to test whether a key exists prior to calling the Add method.

Finally, the example shows how to enumerate the keys and values in the dictionary, and how to enumerate the values alone using the Values property.

Imports System
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main() 

        ' Create a new dictionary of strings, with string keys,  
        ' and access it through the IDictionary generic interface. 
        Dim openWith As IDictionary(Of String, String) = _
            New Dictionary(Of String, String)

        ' Add some elements to the dictionary. There are no  
        ' duplicate keys, but some of the values are duplicates.
        openWith.Add("txt", "notepad.exe")
        openWith.Add("bmp", "paint.exe")
        openWith.Add("dib", "paint.exe")
        openWith.Add("rtf", "wordpad.exe")

        ' The Add method throws an exception if the new key is  
        ' already in the dictionary. 
        Try
            openWith.Add("txt", "winword.exe")
        Catch 
            Console.WriteLine("An element with Key = ""txt"" already exists.")
        End Try 

        ' The Item property is the default property, so you  
        ' can omit its name when accessing elements. 
        Console.WriteLine("For key = ""rtf"", value = {0}.", _
            openWith("rtf"))

        ' The default Item property can be used to change the value 
        ' associated with a key.
        openWith("rtf") = "winword.exe"
        Console.WriteLine("For key = ""rtf"", value = {0}.", _
            openWith("rtf"))

        ' If a key does not exist, setting the default item property 
        ' for that key adds a new key/value pair.
        openWith("doc") = "winword.exe" 

        ' The default Item property throws an exception if the requested 
        ' key is not in the dictionary. 
        Try
            Console.WriteLine("For key = ""tif"", value = {0}.", _
                openWith("tif"))
        Catch 
            Console.WriteLine("Key = ""tif"" is not found.")
        End Try 

        ' When a program often has to try keys that turn out not to 
        ' be in the dictionary, TryGetValue can be a more efficient  
        ' way to retrieve values. 
        Dim value As String = "" 
        If openWith.TryGetValue("tif", value) Then
            Console.WriteLine("For key = ""tif"", value = {0}.", value)
        Else
            Console.WriteLine("Key = ""tif"" is not found.")
        End If 

        ' ContainsKey can be used to test keys before inserting  
        ' them. 
        If Not openWith.ContainsKey("ht") Then
            openWith.Add("ht", "hypertrm.exe")
            Console.WriteLine("Value added for key = ""ht"": {0}", _
                openWith("ht"))
        End If 

        ' When you use foreach to enumerate dictionary elements, 
        ' the elements are retrieved as KeyValuePair objects.
        Console.WriteLine()
        For Each kvp As KeyValuePair(Of String, String) In openWith
            Console.WriteLine("Key = {0}, Value = {1}", _
                kvp.Key, kvp.Value)
        Next kvp

        ' To get the values alone, use the Values property. 
        Dim icoll As ICollection(Of String) = openWith.Values

        ' The elements of the ValueCollection are strongly typed 
        ' with the type that was specified for dictionary values.
        Console.WriteLine()
        For Each s As String In  icoll
            Console.WriteLine("Value = {0}", s)
        Next s

        ' To get the keys alone, use the Keys property.
        icoll = openWith.Keys

        ' The elements of the ValueCollection are strongly typed 
        ' with the type that was specified for dictionary values.
        Console.WriteLine()
        For Each s As String In  icoll
            Console.WriteLine("Key = {0}", s)
        Next s

        ' Use the Remove method to remove a key/value pair.
        Console.WriteLine(vbLf + "Remove(""doc"")")
        openWith.Remove("doc")

        If Not openWith.ContainsKey("doc") Then
            Console.WriteLine("Key ""doc"" is not found.")
        End If 

    End Sub 

End Class 

' This code example produces the following output: 
' 
'An element with Key = "txt" already exists. 
'For key = "rtf", value = wordpad.exe. 
'For key = "rtf", value = winword.exe. 
'Key = "tif" is not found. 
'Key = "tif" is not found. 
'Value added for key = "ht": hypertrm.exe 
' 
'Key = txt, Value = notepad.exe 
'Key = bmp, Value = paint.exe 
'Key = dib, Value = paint.exe 
'Key = rtf, Value = winword.exe 
'Key = doc, Value = winword.exe 
'Key = ht, Value = hypertrm.exe 
' 
'Value = notepad.exe 
'Value = paint.exe 
'Value = paint.exe 
'Value = winword.exe 
'Value = winword.exe 
'Value = hypertrm.exe 
' 
'Key = txt 
'Key = bmp 
'Key = dib 
'Key = rtf 
'Key = doc 
'Key = ht 
' 
'Remove("doc") 
'Key "doc" is not found. 
' 
using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        // Create a new dictionary of strings, with string keys,  
        // and access it through the IDictionary generic interface.
        IDictionary<string, string> openWith = 
            new Dictionary<string, string>();

        // Add some elements to the dictionary. There are no  
        // duplicate keys, but some of the values are duplicates.
        openWith.Add("txt", "notepad.exe");
        openWith.Add("bmp", "paint.exe");
        openWith.Add("dib", "paint.exe");
        openWith.Add("rtf", "wordpad.exe");

        // The Add method throws an exception if the new key is  
        // already in the dictionary. 
        try
        {
            openWith.Add("txt", "winword.exe");
        }
        catch (ArgumentException)
        {
            Console.WriteLine("An element with Key = \"txt\" already exists.");
        }

        // The Item property is another name for the indexer, so you  
        // can omit its name when accessing elements. 
        Console.WriteLine("For key = \"rtf\", value = {0}.", 
            openWith["rtf"]);

        // The indexer can be used to change the value associated 
        // with a key.
        openWith["rtf"] = "winword.exe";
        Console.WriteLine("For key = \"rtf\", value = {0}.", 
            openWith["rtf"]);

        // If a key does not exist, setting the indexer for that key 
        // adds a new key/value pair.
        openWith["doc"] = "winword.exe";

        // The indexer throws an exception if the requested key is 
        // not in the dictionary. 
        try
        {
            Console.WriteLine("For key = \"tif\", value = {0}.", 
                openWith["tif"]);
        }
        catch (KeyNotFoundException)
        {
            Console.WriteLine("Key = \"tif\" is not found.");
        }

        // When a program often has to try keys that turn out not to 
        // be in the dictionary, TryGetValue can be a more efficient  
        // way to retrieve values. 
        string value = "";
        if (openWith.TryGetValue("tif", out value))
        {
            Console.WriteLine("For key = \"tif\", value = {0}.", value);
        }
        else
        {
            Console.WriteLine("Key = \"tif\" is not found.");
        }

        // ContainsKey can be used to test keys before inserting  
        // them. 
        if (!openWith.ContainsKey("ht"))
        {
            openWith.Add("ht", "hypertrm.exe");
            Console.WriteLine("Value added for key = \"ht\": {0}", 
                openWith["ht"]);
        }

        // When you use foreach to enumerate dictionary elements, 
        // the elements are retrieved as KeyValuePair objects.
        Console.WriteLine();
        foreach( KeyValuePair<string, string> kvp in openWith )
        {
            Console.WriteLine("Key = {0}, Value = {1}", 
                kvp.Key, kvp.Value);
        }

        // To get the values alone, use the Values property.
        ICollection<string> icoll = openWith.Values;

        // The elements of the ValueCollection are strongly typed 
        // with the type that was specified for dictionary values.
        Console.WriteLine();
        foreach( string s in icoll )
        {
            Console.WriteLine("Value = {0}", s);
        }

        // To get the keys alone, use the Keys property.
        icoll = openWith.Keys;

        // The elements of the ValueCollection are strongly typed 
        // with the type that was specified for dictionary values.
        Console.WriteLine();
        foreach( string s in icoll )
        {
            Console.WriteLine("Key = {0}", s);
        }

        // Use the Remove method to remove a key/value pair.
        Console.WriteLine("\nRemove(\"doc\")");
        openWith.Remove("doc");

        if (!openWith.ContainsKey("doc"))
        {
            Console.WriteLine("Key \"doc\" is not found.");
        }
    }
}

/* This code example produces the following output:

An element with Key = "txt" already exists.
For key = "rtf", value = wordpad.exe.
For key = "rtf", value = winword.exe.
Key = "tif" is not found.
Key = "tif" is not found.
Value added for key = "ht": hypertrm.exe

Key = txt, Value = notepad.exe
Key = bmp, Value = paint.exe
Key = dib, Value = paint.exe
Key = rtf, Value = winword.exe
Key = doc, Value = winword.exe
Key = ht, Value = hypertrm.exe

Value = notepad.exe
Value = paint.exe
Value = paint.exe
Value = winword.exe
Value = winword.exe
Value = hypertrm.exe

Key = txt
Key = bmp
Key = dib
Key = rtf
Key = doc
Key = ht

Remove("doc")
Key "doc" is not found.
 */
using namespace System;
using namespace System::Collections::Generic;

public ref class Example
{
public:
    static void Main()
    {
        // Create a new dictionary of strings, with string keys, 
        // and access it through the IDictionary generic interface.
        IDictionary<String^, String^>^ openWith =
            gcnew Dictionary<String^, String^>();

        // Add some elements to the dictionary. There are no 
        // duplicate keys, but some of the values are duplicates.
        openWith->Add("txt", "notepad.exe");
        openWith->Add("bmp", "paint.exe");
        openWith->Add("dib", "paint.exe");
        openWith->Add("rtf", "wordpad.exe");

        // The Add method throws an exception if the new key is 
        // already in the dictionary. 
        try
        {
            openWith->Add("txt", "winword.exe");
        }
        catch (ArgumentException^)
        {
            Console::WriteLine("An element with Key = \"txt\" already exists.");
        }

        // The Item property is another name for the indexer, so you 
        // can omit its name when accessing elements.
        Console::WriteLine("For key = \"rtf\", value = {0}.",
            openWith["rtf"]);

        // The indexer can be used to change the value associated 
        // with a key.
        openWith["rtf"] = "winword.exe";
        Console::WriteLine("For key = \"rtf\", value = {0}.",
            openWith["rtf"]);

        // If a key does not exist, setting the indexer for that key 
        // adds a new key/value pair.
        openWith["doc"] = "winword.exe";

        // The indexer throws an exception if the requested key is 
        // not in the dictionary. 
        try
        {
            Console::WriteLine("For key = \"tif\", value = {0}.",
                openWith["tif"]);
        }
        catch (KeyNotFoundException^)
        {
            Console::WriteLine("Key = \"tif\" is not found.");
        }

        // When a program often has to try keys that turn out not to 
        // be in the dictionary, TryGetValue can be a more efficient 
        // way to retrieve values.
        String^ value = "";
        if (openWith->TryGetValue("tif", value))
        {
            Console::WriteLine("For key = \"tif\", value = {0}.", value);
        }
        else
        {
            Console::WriteLine("Key = \"tif\" is not found.");
        }

        // ContainsKey can be used to test keys before inserting 
        // them. 
        if (!openWith->ContainsKey("ht"))
        {
            openWith->Add("ht", "hypertrm.exe");
            Console::WriteLine("Value added for key = \"ht\": {0}",
                openWith["ht"]);
        }

        // When you use foreach to enumerate dictionary elements, 
        // the elements are retrieved as KeyValuePair objects.
        Console::WriteLine();
        for each( KeyValuePair<String^, String^> kvp in openWith )
        {
            Console::WriteLine("Key = {0}, Value = {1}",
                kvp.Key, kvp.Value);
        }

        // To get the values alone, use the Values property.
        ICollection<String^>^ icoll = openWith->Values;

        // The elements of the ValueCollection are strongly typed 
        // with the type that was specified for dictionary values.
        Console::WriteLine();
        for each( String^ s in icoll )
        {
            Console::WriteLine("Value = {0}", s);
        }

        // To get the keys alone, use the Keys property.
        icoll = openWith->Keys;

        // The elements of the ValueCollection are strongly typed 
        // with the type that was specified for dictionary values.
        Console::WriteLine();
        for each( String^ s in icoll )
        {
            Console::WriteLine("Key = {0}", s);
        }

        // Use the Remove method to remove a key/value pair.
        Console::WriteLine("\nRemove(\"doc\")");
        openWith->Remove("doc");

        if (!openWith->ContainsKey("doc"))
        {
            Console::WriteLine("Key \"doc\" is not found.");
        }
    }
};

int main()
{
    Example::Main();
}

/* This code example produces the following output:

An element with Key = "txt" already exists.
For key = "rtf", value = wordpad.exe.
For key = "rtf", value = winword.exe.
Key = "tif" is not found.
Key = "tif" is not found.
Value added for key = "ht": hypertrm.exe

Key = txt, Value = notepad.exe
Key = bmp, Value = paint.exe
Key = dib, Value = paint.exe
Key = rtf, Value = winword.exe
Key = doc, Value = winword.exe
Key = ht, Value = hypertrm.exe

Value = notepad.exe
Value = paint.exe
Value = paint.exe
Value = winword.exe
Value = winword.exe
Value = hypertrm.exe

Key = txt
Key = bmp
Key = dib
Key = rtf
Key = doc
Key = ht

Remove("doc")
Key "doc" is not found.
 */
Version Information

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8