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List Class
 

Represents a strongly typed list of objects that can be accessed by index. Provides methods to search, sort, and manipulate lists.

To browse the .NET Framework source code for this type, see the Reference Source.

Namespace:   System.Collections.Generic
Assembly:  mscorlib (in mscorlib.dll)


Syntax
[SerializableAttribute]
public class List<T> : IList<T>, ICollection<T>, IEnumerable<T>, 
	IEnumerable, IList, ICollection, IReadOnlyList<T>, IReadOnlyCollection<T>
generic<typename T>
[SerializableAttribute]
public ref class List : IList<T>, ICollection<T>, IEnumerable<T>, 
	IEnumerable, IList, ICollection, IReadOnlyList<T>, IReadOnlyCollection<T>
[<SerializableAttribute>]
type List<'T> = 
    class
        interface IList<'T>
        interface ICollection<'T>
        interface IEnumerable<'T>
        interface IEnumerable
        interface IList
        interface ICollection
        interface IReadOnlyList<'T>
        interface IReadOnlyCollection<'T>
    end
<SerializableAttribute>
Public Class List(Of T)
	Implements IList(Of T), ICollection(Of T), IEnumerable(Of T), IEnumerable,
	IList, ICollection, IReadOnlyList(Of T), IReadOnlyCollection(Of T)

Type Parameters

T

The type of elements in the list.

Constructors
NameDescription
System_CAPS_pubmethod List

Initializes a new instance of the List class that is empty and has the default initial capacity.

System_CAPS_pubmethod List

Initializes a new instance of the List class that contains elements copied from the specified collection and has sufficient capacity to accommodate the number of elements copied.

System_CAPS_pubmethod List

Initializes a new instance of the List class that is empty and has the specified initial capacity.

Properties
NameDescription
System_CAPS_pubproperty

Gets or sets the total number of elements the internal data structure can hold without resizing.

System_CAPS_pubproperty

Gets the number of elements contained in the List.

System_CAPS_pubproperty

Gets or sets the element at the specified index.

Methods
NameDescription
System_CAPS_pubmethod Add

Adds an object to the end of the List.

System_CAPS_pubmethod AddRange

Adds the elements of the specified collection to the end of the List.

System_CAPS_pubmethod AsReadOnly

Returns a read-only ReadOnlyCollection wrapper for the current collection.

System_CAPS_pubmethod BinarySearch

Searches the entire sorted List for an element using the default comparer and returns the zero-based index of the element.

System_CAPS_pubmethod BinarySearch

Searches the entire sorted List for an element using the specified comparer and returns the zero-based index of the element.

System_CAPS_pubmethod BinarySearch

Searches a range of elements in the sorted List for an element using the specified comparer and returns the zero-based index of the element.

System_CAPS_pubmethod Clear

Removes all elements from the List.

System_CAPS_pubmethod Contains

Determines whether an element is in the List.

System_CAPS_pubmethod ConvertAll

Converts the elements in the current List to another type, and returns a list containing the converted elements.

System_CAPS_pubmethod CopyTo

Copies the entire List to a compatible one-dimensional array, starting at the beginning of the target array.

System_CAPS_pubmethod CopyTo

Copies the entire List to a compatible one-dimensional array, starting at the specified index of the target array.

System_CAPS_pubmethod CopyTo

Copies a range of elements from the List to a compatible one-dimensional array, starting at the specified index of the target array.

System_CAPS_pubmethod Equals

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethod Exists

Determines whether the List contains elements that match the conditions defined by the specified predicate.

System_CAPS_protmethod Finalize

Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.)

System_CAPS_pubmethod Find

Searches for an element that matches the conditions defined by the specified predicate, and returns the first occurrence within the entire List.

System_CAPS_pubmethod FindAll

Retrieves all the elements that match the conditions defined by the specified predicate.

System_CAPS_pubmethod FindIndex

Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the range of elements in the List that starts at the specified index and contains the specified number of elements.

System_CAPS_pubmethod FindIndex

Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the range of elements in the List that extends from the specified index to the last element.

System_CAPS_pubmethod FindIndex

Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the first occurrence within the entire List.

System_CAPS_pubmethod FindLast

Searches for an element that matches the conditions defined by the specified predicate, and returns the last occurrence within the entire List.

System_CAPS_pubmethod FindLastIndex

Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the last occurrence within the range of elements in the List that contains the specified number of elements and ends at the specified index.

System_CAPS_pubmethod FindLastIndex

Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the last occurrence within the range of elements in the List that extends from the first element to the specified index.

System_CAPS_pubmethod FindLastIndex

Searches for an element that matches the conditions defined by the specified predicate, and returns the zero-based index of the last occurrence within the entire List.

System_CAPS_pubmethod ForEach

Performs the specified action on each element of the List.

System_CAPS_pubmethod GetEnumerator

Returns an enumerator that iterates through the List.

System_CAPS_pubmethod GetHashCode

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethod GetRange

Creates a shallow copy of a range of elements in the source List.

System_CAPS_pubmethod GetType

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethod IndexOf

Searches for the specified object and returns the zero-based index of the first occurrence within the entire List.

System_CAPS_pubmethod IndexOf

Searches for the specified object and returns the zero-based index of the first occurrence within the range of elements in the List that extends from the specified index to the last element.

System_CAPS_pubmethod IndexOf

Searches for the specified object and returns the zero-based index of the first occurrence within the range of elements in the List that starts at the specified index and contains the specified number of elements.

System_CAPS_pubmethod Insert

Inserts an element into the List at the specified index.

System_CAPS_pubmethod InsertRange

Inserts the elements of a collection into the List at the specified index.

System_CAPS_pubmethod LastIndexOf

Searches for the specified object and returns the zero-based index of the last occurrence within the entire List.

System_CAPS_pubmethod LastIndexOf

Searches for the specified object and returns the zero-based index of the last occurrence within the range of elements in the List that extends from the first element to the specified index.

System_CAPS_pubmethod LastIndexOf

Searches for the specified object and returns the zero-based index of the last occurrence within the range of elements in the List that contains the specified number of elements and ends at the specified index.

System_CAPS_protmethod MemberwiseClone

Creates a shallow copy of the current Object.(Inherited from Object.)

System_CAPS_pubmethod Remove

Removes the first occurrence of a specific object from the List.

System_CAPS_pubmethod RemoveAll

Removes all the elements that match the conditions defined by the specified predicate.

System_CAPS_pubmethod RemoveAt

Removes the element at the specified index of the List.

System_CAPS_pubmethod RemoveRange

Removes a range of elements from the List.

System_CAPS_pubmethod Reverse

Reverses the order of the elements in the entire List.

System_CAPS_pubmethod Reverse

Reverses the order of the elements in the specified range.

System_CAPS_pubmethod Sort

Sorts the elements in the entire List using the default comparer.

System_CAPS_pubmethod Sort

Sorts the elements in the entire List using the specified SystemComparison.

System_CAPS_pubmethod Sort

Sorts the elements in the entire List using the specified comparer.

System_CAPS_pubmethod Sort

Sorts the elements in a range of elements in List using the specified comparer.

System_CAPS_pubmethod ToArray

Copies the elements of the List to a new array.

System_CAPS_pubmethod ToString

Returns a string that represents the current object.(Inherited from Object.)

System_CAPS_pubmethod TrimExcess

Sets the capacity to the actual number of elements in the List, if that number is less than a threshold value.

System_CAPS_pubmethod TrueForAll

Determines whether every element in the List matches the conditions defined by the specified predicate.

Explicit Interface Implementations
NameDescription
System_CAPS_pubinterface System_CAPS_privmethod IEnumerableGetEnumerator

Returns an enumerator that iterates through a collection.

System_CAPS_pubinterface System_CAPS_privmethod ICollectionCopyTo

Copies the elements of the ICollection to an Array, starting at a particular Array index.

System_CAPS_pubinterface System_CAPS_privmethod IEnumerableGetEnumerator

Returns an enumerator that iterates through a collection.

System_CAPS_pubinterface System_CAPS_privmethod IListAdd

Adds an item to the IList.

System_CAPS_pubinterface System_CAPS_privmethod IListContains

Determines whether the IList contains a specific value.

System_CAPS_pubinterface System_CAPS_privmethod IListIndexOf

Determines the index of a specific item in the IList.

System_CAPS_pubinterface System_CAPS_privmethod IListInsert

Inserts an item to the IList at the specified index.

System_CAPS_pubinterface System_CAPS_privmethod IListRemove

Removes the first occurrence of a specific object from the IList.

System_CAPS_pubinterface System_CAPS_privproperty

Gets a value indicating whether the ICollection is read-only.

System_CAPS_pubinterface System_CAPS_privproperty

Gets a value indicating whether access to the ICollection is synchronized (thread safe).

System_CAPS_pubinterface System_CAPS_privproperty

Gets an object that can be used to synchronize access to the ICollection.

System_CAPS_pubinterface System_CAPS_privproperty

Gets a value indicating whether the IList has a fixed size.

System_CAPS_pubinterface System_CAPS_privproperty

Gets a value indicating whether the IList is read-only.

System_CAPS_pubinterface System_CAPS_privproperty

Gets or sets the element at the specified index.

Extension Methods
NameDescription
System_CAPS_pubmethod Aggregate

Overloaded. Applies an accumulator function over a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Aggregate

Overloaded. Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value.(Defined by Enumerable.)

System_CAPS_pubmethod Aggregate

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.)

System_CAPS_pubmethod All

Determines whether all elements of a sequence satisfy a condition.(Defined by Enumerable.)

System_CAPS_pubmethod Any

Overloaded. Determines whether a sequence contains any elements.(Defined by Enumerable.)

System_CAPS_pubmethod Any

Overloaded. Determines whether any element of a sequence satisfies a condition.(Defined by Enumerable.)

System_CAPS_pubmethod AsEnumerable

Returns the input typed as IEnumerable.(Defined by Enumerable.)

System_CAPS_pubmethod AsParallel

Overloaded. Enables parallelization of a query.(Defined by ParallelEnumerable.)

System_CAPS_pubmethod AsParallel

Overloaded. Enables parallelization of a query.(Defined by ParallelEnumerable.)

System_CAPS_pubmethod AsQueryable

Overloaded. Converts an IEnumerable to an IQueryable.(Defined by Queryable.)

System_CAPS_pubmethod AsQueryable

Overloaded. Converts a generic IEnumerable to a generic IQueryable.(Defined by Queryable.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Average

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.)

System_CAPS_pubmethod Cast

Casts the elements of an IEnumerable to the specified type.(Defined by Enumerable.)

System_CAPS_pubmethod Concat

Concatenates two sequences.(Defined by Enumerable.)

System_CAPS_pubmethod Contains

Overloaded. Determines whether a sequence contains a specified element by using the default equality comparer.(Defined by Enumerable.)

System_CAPS_pubmethod Contains

Overloaded. Determines whether a sequence contains a specified element by using a specified IEqualityComparer.(Defined by Enumerable.)

System_CAPS_pubmethod Count

Overloaded. Returns the number of elements in a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Count

Overloaded. Returns a number that represents how many elements in the specified sequence satisfy a condition.(Defined by Enumerable.)

System_CAPS_pubmethod DefaultIfEmpty

Overloaded. 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.)

System_CAPS_pubmethod DefaultIfEmpty

Overloaded. Returns the elements of the specified sequence or the specified value in a singleton collection if the sequence is empty.(Defined by Enumerable.)

System_CAPS_pubmethod Distinct

Overloaded. Returns distinct elements from a sequence by using the default equality comparer to compare values.(Defined by Enumerable.)

System_CAPS_pubmethod Distinct

Overloaded. Returns distinct elements from a sequence by using a specified IEqualityComparer to compare values.(Defined by Enumerable.)

System_CAPS_pubmethod ElementAt

Returns the element at a specified index in a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod ElementAtOrDefault

Returns the element at a specified index in a sequence or a default value if the index is out of range.(Defined by Enumerable.)

System_CAPS_pubmethod Except

Overloaded. Produces the set difference of two sequences by using the default equality comparer to compare values.(Defined by Enumerable.)

System_CAPS_pubmethod Except

Overloaded. Produces the set difference of two sequences by using the specified IEqualityComparer to compare values.(Defined by Enumerable.)

System_CAPS_pubmethod First

Overloaded. Returns the first element of a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod First

Overloaded. Returns the first element in a sequence that satisfies a specified condition.(Defined by Enumerable.)

System_CAPS_pubmethod FirstOrDefault

Overloaded. Returns the first element of a sequence, or a default value if the sequence contains no elements.(Defined by Enumerable.)

System_CAPS_pubmethod FirstOrDefault

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.)

System_CAPS_pubmethod GroupBy

Overloaded. Groups the elements of a sequence according to a specified key selector function.(Defined by Enumerable.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupBy

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.)

System_CAPS_pubmethod GroupJoin

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.)

System_CAPS_pubmethod GroupJoin

Overloaded. Correlates the elements of two sequences based on key equality and groups the results. A specified IEqualityComparer is used to compare keys.(Defined by Enumerable.)

System_CAPS_pubmethod Intersect

Overloaded. Produces the set intersection of two sequences by using the default equality comparer to compare values.(Defined by Enumerable.)

System_CAPS_pubmethod Intersect

Overloaded. Produces the set intersection of two sequences by using the specified IEqualityComparer to compare values.(Defined by Enumerable.)

System_CAPS_pubmethod Join

Overloaded. Correlates the elements of two sequences based on matching keys. The default equality comparer is used to compare keys.(Defined by Enumerable.)

System_CAPS_pubmethod Join

Overloaded. Correlates the elements of two sequences based on matching keys. A specified IEqualityComparer is used to compare keys.(Defined by Enumerable.)

System_CAPS_pubmethod Last

Overloaded. Returns the last element of a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Last

Overloaded. Returns the last element of a sequence that satisfies a specified condition.(Defined by Enumerable.)

System_CAPS_pubmethod LastOrDefault

Overloaded. Returns the last element of a sequence, or a default value if the sequence contains no elements.(Defined by Enumerable.)

System_CAPS_pubmethod LastOrDefault

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.)

System_CAPS_pubmethod LongCount

Overloaded. Returns an Int64 that represents the total number of elements in a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod LongCount

Overloaded. Returns an Int64 that represents how many elements in a sequence satisfy a condition.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Returns the maximum value in a generic sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Decimal value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Double value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Int32 value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Int64 value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Decimal value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Double value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Int32 value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Int64 value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum nullable Single value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a sequence and returns the maximum Single value.(Defined by Enumerable.)

System_CAPS_pubmethod Max

Overloaded. Invokes a transform function on each element of a generic sequence and returns the maximum resulting value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Returns the minimum value in a generic sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Decimal value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Double value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Int32 value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Int64 value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Decimal value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Double value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Int32 value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Int64 value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum nullable Single value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a sequence and returns the minimum Single value.(Defined by Enumerable.)

System_CAPS_pubmethod Min

Overloaded. Invokes a transform function on each element of a generic sequence and returns the minimum resulting value.(Defined by Enumerable.)

System_CAPS_pubmethod OfType

Filters the elements of an IEnumerable based on a specified type.(Defined by Enumerable.)

System_CAPS_pubmethod OrderBy

Overloaded. Sorts the elements of a sequence in ascending order according to a key.(Defined by Enumerable.)

System_CAPS_pubmethod OrderBy

Overloaded. Sorts the elements of a sequence in ascending order by using a specified comparer.(Defined by Enumerable.)

System_CAPS_pubmethod OrderByDescending

Overloaded. Sorts the elements of a sequence in descending order according to a key.(Defined by Enumerable.)

System_CAPS_pubmethod OrderByDescending

Overloaded. Sorts the elements of a sequence in descending order by using a specified comparer.(Defined by Enumerable.)

System_CAPS_pubmethod Reverse

Inverts the order of the elements in a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Select

Overloaded. Projects each element of a sequence into a new form.(Defined by Enumerable.)

System_CAPS_pubmethod Select

Overloaded. Projects each element of a sequence into a new form by incorporating the element's index.(Defined by Enumerable.)

System_CAPS_pubmethod SelectMany

Overloaded. Projects each element of a sequence to an IEnumerable and flattens the resulting sequences into one sequence.(Defined by Enumerable.)

System_CAPS_pubmethod SelectMany

Overloaded. Projects each element of a sequence to an IEnumerable, 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.)

System_CAPS_pubmethod SelectMany

Overloaded. Projects each element of a sequence to an IEnumerable, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein.(Defined by Enumerable.)

System_CAPS_pubmethod SelectMany

Overloaded. Projects each element of a sequence to an IEnumerable, 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.)

System_CAPS_pubmethod SequenceEqual

Overloaded. Determines whether two sequences are equal by comparing the elements by using the default equality comparer for their type.(Defined by Enumerable.)

System_CAPS_pubmethod SequenceEqual

Overloaded. Determines whether two sequences are equal by comparing their elements by using a specified IEqualityComparer.(Defined by Enumerable.)

System_CAPS_pubmethod Single

Overloaded. Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence.(Defined by Enumerable.)

System_CAPS_pubmethod Single

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.)

System_CAPS_pubmethod SingleOrDefault

Overloaded. 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.)

System_CAPS_pubmethod SingleOrDefault

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.)

System_CAPS_pubmethod Skip

Bypasses a specified number of elements in a sequence and then returns the remaining elements.(Defined by Enumerable.)

System_CAPS_pubmethod SkipWhile

Overloaded. Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements.(Defined by Enumerable.)

System_CAPS_pubmethod SkipWhile

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Sum

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.)

System_CAPS_pubmethod Take

Returns a specified number of contiguous elements from the start of a sequence.(Defined by Enumerable.)

System_CAPS_pubmethod TakeWhile

Overloaded. Returns elements from a sequence as long as a specified condition is true.(Defined by Enumerable.)

System_CAPS_pubmethod TakeWhile

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.)

System_CAPS_pubmethod ToArray

Creates an array from a IEnumerable.(Defined by Enumerable.)

System_CAPS_pubmethod ToDictionary

Overloaded. Creates a Dictionary from an IEnumerable according to a specified key selector function.(Defined by Enumerable.)

System_CAPS_pubmethod ToDictionary

Overloaded. Creates a Dictionary from an IEnumerable according to a specified key selector function and key comparer.(Defined by Enumerable.)

System_CAPS_pubmethod ToDictionary

Overloaded. Creates a Dictionary from an IEnumerable according to specified key selector and element selector functions.(Defined by Enumerable.)

System_CAPS_pubmethod ToDictionary

Overloaded. Creates a Dictionary from an IEnumerable according to a specified key selector function, a comparer, and an element selector function.(Defined by Enumerable.)

System_CAPS_pubmethod ToList

Creates a List from an IEnumerable.(Defined by Enumerable.)

System_CAPS_pubmethod ToLookup

Overloaded. Creates a Lookup from an IEnumerable according to a specified key selector function.(Defined by Enumerable.)

System_CAPS_pubmethod ToLookup

Overloaded. Creates a Lookup from an IEnumerable according to a specified key selector function and key comparer.(Defined by Enumerable.)

System_CAPS_pubmethod ToLookup

Overloaded. Creates a Lookup from an IEnumerable according to specified key selector and element selector functions.(Defined by Enumerable.)

System_CAPS_pubmethod ToLookup

Overloaded. Creates a Lookup from an IEnumerable according to a specified key selector function, a comparer and an element selector function.(Defined by Enumerable.)

System_CAPS_pubmethod Union

Overloaded. Produces the set union of two sequences by using the default equality comparer.(Defined by Enumerable.)

System_CAPS_pubmethod Union

Overloaded. Produces the set union of two sequences by using a specified IEqualityComparer.(Defined by Enumerable.)

System_CAPS_pubmethod Where

Overloaded. Filters a sequence of values based on a predicate.(Defined by Enumerable.)

System_CAPS_pubmethod Where

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.)

System_CAPS_pubmethod Zip

Applies a specified function to the corresponding elements of two sequences, producing a sequence of the results.(Defined by Enumerable.)

Remarks
System_CAPS_noteNote

To view the .NET Framework source code for this type, see the Reference Source. You can browse through the source code online, download the reference for offline viewing, and step through the sources (including patches and updates) during debugging; see instructions.

The List class is the generic equivalent of the ArrayList class. It implements the IList generic interface by using an array whose size is dynamically increased as required.

You can add items to a List by using the Add or AddRange methods.

The List class uses both an equality comparer and an ordering comparer.

  • Methods such as Contains, IndexOf, LastIndexOf, and Remove use an equality comparer for the list elements. The default equality comparer for type T is determined as follows. If type T implements the IEquatable generic interface, then the equality comparer is the Equals method of that interface; otherwise, the default equality comparer is ObjectEquals.

  • Methods such as BinarySearch and Sort use an ordering comparer for the list elements. The default comparer for type T is determined as follows. If type T implements the IComparable generic interface, then the default comparer is the CompareTo method of that interface; otherwise, if type T implements the nongeneric IComparable interface, then the default comparer is the CompareTo method of that interface. If type T implements neither interface, then there is no default comparer, and a comparer or comparison delegate must be provided explicitly.

The List is not guaranteed to be sorted. You must sort the List before performing operations (such as BinarySearch) that require the List to be sorted.

Elements in this collection can be accessed using an integer index. Indexes in this collection are zero-based.

For very large List objects, you can increase the maximum capacity to 2 billion elements on a 64-bit system by setting the enabled attribute of the configuration element to true in the run-time environment.

List accepts null as a valid value for reference types and allows duplicate elements.

For an immutable version of the List class, see ImmutableList.

Performance Considerations

In deciding whether to use the List or ArrayList class, both of which have similar functionality, remember that the List class performs better in most cases and is type safe. If a reference type is used for type T of the List class, the behavior of the two classes is identical. However, if a value type is used for type T, you need to consider implementation and boxing issues.

If a value type is used for type T, the compiler generates an implementation of the List class specifically for that value type. That means a list element of a List object does not have to be boxed before the element can be used, and after about 500 list elements are created the memory saved not boxing list elements is greater than the memory used to generate the class implementation.

Make certain the value type used for type T implements the IEquatable generic interface. If not, methods such as Contains must call the ObjectEquals method, which boxes the affected list element. If the value type implements the IComparable interface and you own the source code, also implement the IComparable generic interface to prevent the BinarySearch and Sort methods from boxing list elements. If you do not own the source code, pass an IComparer object to the BinarySearch and Sort methods

It is to your advantage to use the type-specific implementation of the List class instead of using the ArrayList class or writing a strongly typed wrapper collection yourself. The reason is your implementation must do what the .NET Framework does for you already, and the common language runtime can share Microsoft intermediate language code and metadata, which your implementation cannot.

F# Considerations

The List class is used infrequently in F# code. Instead, Lists (F#), which are immutable, singly-linked lists, are typically preferred. An F# List provides an ordered, immutable series of values, and is supported for use in functional-style development. When used from F#, theList class is typically referred to by the ResizeArray<'T> type abbreviation to avoid naming conflicts with F# Lists

Examples

The following example demonstrates how to add, remove, and insert a simple business object in a List.

using System;
using System.Collections.Generic;
// Simple business object. A PartId is used to identify the type of part 
// but the part name can change. 
public class Part : IEquatable<Part>
    {
        public string PartName { get; set; }

        public int PartId { get; set; }

        public override string ToString()
        {
            return "ID: " + PartId + "   Name: " + PartName;
        }
        public override bool Equals(object obj)
        {
            if (obj == null) return false;
            Part objAsPart = obj as Part;
            if (objAsPart == null) return false;
            else return Equals(objAsPart);
        }
        public override int GetHashCode()
        {
            return PartId;
        }
        public bool Equals(Part other)
        {
            if (other == null) return false;
            return (this.PartId.Equals(other.PartId));
        }
    // Should also override == and != operators.

    }
public class Example
{
    public static void Main()
    {
        // Create a list of parts.
        List<Part> parts = new List<Part>();

        // Add parts to the list.
        parts.Add(new Part() {PartName="crank arm", PartId=1234});
        parts.Add(new Part() { PartName = "chain ring", PartId = 1334 });
        parts.Add(new Part() { PartName = "regular seat", PartId = 1434 });
        parts.Add(new Part() { PartName = "banana seat", PartId = 1444 });
        parts.Add(new Part() { PartName = "cassette", PartId = 1534 });
        parts.Add(new Part() { PartName = "shift lever", PartId = 1634 });

        // Write out the parts in the list. This will call the overridden ToString method
        // in the Part class.
        Console.WriteLine();
        foreach (Part aPart in parts)
        {
            Console.WriteLine(aPart);
        }


        // Check the list for part #1734. This calls the IEquitable.Equals method
        // of the Part class, which checks the PartId for equality.
        Console.WriteLine("\nContains(\"1734\"): {0}",
        parts.Contains(new Part {PartId=1734, PartName="" }));

        // Insert a new item at position 2.
        Console.WriteLine("\nInsert(2, \"1834\")");
        parts.Insert(2, new Part() { PartName = "brake lever", PartId = 1834 });


        //Console.WriteLine();
        foreach (Part aPart in parts)
        {
            Console.WriteLine(aPart);
        }

        Console.WriteLine("\nParts[3]: {0}", parts[3]);

        Console.WriteLine("\nRemove(\"1534\")");

        // This will remove part 1534 even though the PartName is different,
        // because the Equals method only checks PartId for equality.
        parts.Remove(new Part(){PartId=1534, PartName="cogs"});

        Console.WriteLine();
        foreach (Part aPart in parts)
        {
            Console.WriteLine(aPart);
        }
        Console.WriteLine("\nRemoveAt(3)");
        // This will remove the part at index 3.
        parts.RemoveAt(3);

        Console.WriteLine();
        foreach (Part aPart in parts)
        {
            Console.WriteLine(aPart);
        }

            /*

             ID: 1234   Name: crank arm
             ID: 1334   Name: chain ring
             ID: 1434   Name: regular seat
             ID: 1444   Name: banana seat
             ID: 1534   Name: cassette
             ID: 1634   Name: shift lever

             Contains("1734"): False

             Insert(2, "1834")
             ID: 1234   Name: crank arm
             ID: 1334   Name: chain ring
             ID: 1834   Name: brake lever
             ID: 1434   Name: regular seat
             ID: 1444   Name: banana seat
             ID: 1534   Name: cassette
             ID: 1634   Name: shift lever

             Parts[3]: ID: 1434   Name: regular seat

             Remove("1534")

             ID: 1234   Name: crank arm
             ID: 1334   Name: chain ring
             ID: 1834   Name: brake lever
             ID: 1434   Name: regular seat
             ID: 1444   Name: banana seat
             ID: 1634   Name: shift lever

             RemoveAt(3)

             ID: 1234   Name: crank arm
             ID: 1334   Name: chain ring
             ID: 1834   Name: brake lever
             ID: 1444   Name: banana seat
             ID: 1634   Name: shift lever


         */

    }
}
Imports System.Collections.Generic
' Simple business object. A PartId is used to identify the type of part 
' but the part name can change. 
Public Class Part
    Implements IEquatable(Of Part)
    Public Property PartName() As String
        Get
            Return m_PartName
        End Get
        Set(value As String)
            m_PartName = Value
        End Set
    End Property
    Private m_PartName As String

    Public Property PartId() As Integer
        Get
            Return m_PartId
        End Get
        Set(value As Integer)
            m_PartId = Value
        End Set
    End Property
    Private m_PartId As Integer

    Public Overrides Function ToString() As String
        Return "ID: " & PartId & "   Name: " & PartName
    End Function
    Public Overrides Function Equals(obj As Object) As Boolean
        If obj Is Nothing Then
            Return False
        End If
        Dim objAsPart As Part = TryCast(obj, Part)
        If objAsPart Is Nothing Then
            Return False
        Else
            Return Equals(objAsPart)
        End If
    End Function
    Public Overrides Function GetHashCode() As Integer
        Return PartId
    End Function
    Public Overloads Function Equals(other As Part) As Boolean _
        Implements IEquatable(Of Part).Equals
        If other Is Nothing Then
            Return False
        End If
        Return (Me.PartId.Equals(other.PartId))
    End Function
    ' Should also override == and != operators.

End Class
Public Class Example
    Public Shared Sub Main()
        ' Create a list of parts.
        Dim parts As New List(Of Part)()

        ' Add parts to the list.
        parts.Add(New Part() With { _
             .PartName = "crank arm", _
             .PartId = 1234 _
        })
        parts.Add(New Part() With { _
             .PartName = "chain ring", _
             .PartId = 1334 _
        })
        parts.Add(New Part() With { _
             .PartName = "regular seat", _
             .PartId = 1434 _
        })
        parts.Add(New Part() With { _
             .PartName = "banana seat", _
             .PartId = 1444 _
        })
        parts.Add(New Part() With { _
             .PartName = "cassette", _
             .PartId = 1534 _
        })
        parts.Add(New Part() With { _
             .PartName = "shift lever", _
             .PartId = 1634 _
        })



        ' Write out the parts in the list. This will call the overridden ToString method
        ' in the Part class.
        Console.WriteLine()
        For Each aPart As Part In parts
            Console.WriteLine(aPart)
        Next


        ' Check the list for part #1734. This calls the IEquitable.Equals method
        ' of the Part class, which checks the PartId for equality.
        Console.WriteLine(vbLf & "Contains(""1734""): {0}", parts.Contains(New Part() With { _
             .PartId = 1734, _
             .PartName = "" _
        }))

        ' Insert a new item at position 2.
        Console.WriteLine(vbLf & "Insert(2, ""1834"")")
        parts.Insert(2, New Part() With { _
             .PartName = "brake lever", _
             .PartId = 1834 _
        })


        'Console.WriteLine();
        For Each aPart As Part In parts
            Console.WriteLine(aPart)
        Next

        Console.WriteLine(vbLf & "Parts[3]: {0}", parts(3))

        Console.WriteLine(vbLf & "Remove(""1534"")")

        ' This will remove part 1534 even though the PartName is different,
        ' because the Equals method only checks PartId for equality.
        parts.Remove(New Part() With { _
             .PartId = 1534, _
             .PartName = "cogs" _
        })

        Console.WriteLine()
        For Each aPart As Part In parts
            Console.WriteLine(aPart)
        Next

        Console.WriteLine(vbLf & "RemoveAt(3)")
        ' This will remove part at index 3.
        parts.RemoveAt(3)

        Console.WriteLine()
        For Each aPart As Part In parts
            Console.WriteLine(aPart)
        Next
    End Sub
    '
    '        This example code produces the following output:
    '        ID: 1234   Name: crank arm
    '        ID: 1334   Name: chain ring
    '        ID: 1434   Name: regular seat
    '        ID: 1444   Name: banana seat
    '        ID: 1534   Name: cassette
    '        ID: 1634   Name: shift lever
    '
    '        Contains("1734"): False
    '
    '        Insert(2, "1834")
    '        ID: 1234   Name: crank arm
    '        ID: 1334   Name: chain ring
    '        ID: 1834   Name: brake lever
    '        ID: 1434   Name: regular seat
    '        ID: 1444   Name: banana seat
    '        ID: 1534   Name: cassette
    '        ID: 1634   Name: shift lever
    '
    '        Parts[3]: ID: 1434   Name: regular seat
    '
    '        Remove("1534")
    '
    '        ID: 1234   Name: crank arm
    '        ID: 1334   Name: chain ring
    '        ID: 1834   Name: brake lever
    '        ID: 1434   Name: regular seat
    '        ID: 1444   Name: banana seat
    '        ID: 1634   Name: shift lever
    '   '
    '        RemoveAt(3)
    '
    '        ID: 1234   Name: crank arm
    '        ID: 1334   Name: chain ring
    '        ID: 1834   Name: brake lever
    '        ID: 1444   Name: banana seat
    '        ID: 1634   Name: shift lever
    '        

End Class

// Simple business object. A PartId is used to identify the type of part  
// but the part name can change.  
[<CustomEquality; NoComparison>]
type Part = { PartId : int ; mutable PartName : string } with
    override this.GetHashCode() = hash this.PartId
    override this.Equals(other) =
        match other with
        | :? Part as p -> this.PartId = p.PartId
        | _ -> false
    override this.ToString() = sprintf "ID: %i   Name: %s" this.PartId this.PartName

[<EntryPoint>]
let main argv = 
    // We refer to System.Collections.Generic.List<'T> by its type 
    // abbreviation ResizeArray<'T> to avoid conflicts with the F# List module.    
    // Note: In F# code, F# linked lists are usually preferred over
    // ResizeArray<'T> when an extendable collection is required.
    let parts = ResizeArray<_>()
    parts.Add({PartName = "crank arm" ; PartId = 1234})
    parts.Add({PartName = "chain ring"; PartId = 1334 })
    parts.Add({PartName = "regular seat"; PartId = 1434 })
    parts.Add({PartName = "banana seat"; PartId = 1444 })
    parts.Add({PartName = "cassette"; PartId = 1534 })
    parts.Add({PartName = "shift lever"; PartId = 1634 })

    // Write out the parts in the ResizeArray.  This will call the overridden ToString method
    // in the Part type
    printfn ""
    parts |> Seq.iter (fun p -> printfn "%O" p)

    // Check the ResizeArray for part #1734. This calls the IEquatable.Equals method 
    // of the Part type, which checks the PartId for equality.    
    printfn "\nContains(\"1734\"): %b" (parts.Contains({PartId=1734; PartName=""}))

    // Insert a new item at position 2.
    printfn "\nInsert(2, \"1834\")"
    parts.Insert(2, { PartName = "brake lever"; PartId = 1834 })

    // Write out all parts
    parts |> Seq.iter (fun p -> printfn "%O" p)

    printfn "\nParts[3]: %O" parts.[3]

    printfn "\nRemove(\"1534\")"
    // This will remove part 1534 even though the PartName is different, 
    // because the Equals method only checks PartId for equality.
    // Since Remove returns true or false, we need to ignore the result
    parts.Remove({PartId=1534; PartName="cogs"}) |> ignore

    // Write out all parts
    printfn ""
    parts |> Seq.iter (fun p -> printfn "%O" p)

    printfn "\nRemoveAt(3)"
    // This will remove the part at index 3.
    parts.RemoveAt(3)

    // Write out all parts
    printfn ""
    parts |> Seq.iter (fun p -> printfn "%O" p)

    0 // return an integer exit code

The following example demonstrates several properties and methods of the List generic class of type string. (For an example of a List of complex types, see the Contains method.)

The default constructor is used to create a list of strings with the default capacity. The property is displayed and then the Add method is used to add several items. The items are listed, and the property is displayed again, along with the property, to show that the capacity has been increased as needed.

The Contains method is used to test for the presence of an item in the list, the Insert method is used to insert a new item in the middle of the list, and the contents of the list are displayed again.

The default property (the indexer in C#) is used to retrieve an item, the Remove method is used to remove the first instance of the duplicate item added earlier, and the contents are displayed again. The Remove method always removes the first instance it encounters.

The TrimExcess method is used to reduce the capacity to match the count, and the and properties are displayed. If the unused capacity had been less than 10 percent of total capacity, the list would not have been resized.

Finally, the Clear method is used to remove all items from the list, and the and properties are displayed.

using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        List<string> dinosaurs = new List<string>();

        Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);

        dinosaurs.Add("Tyrannosaurus");
        dinosaurs.Add("Amargasaurus");
        dinosaurs.Add("Mamenchisaurus");
        dinosaurs.Add("Deinonychus");
        dinosaurs.Add("Compsognathus");
        Console.WriteLine();
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        Console.WriteLine("\nCapacity: {0}", dinosaurs.Capacity);
        Console.WriteLine("Count: {0}", dinosaurs.Count);

        Console.WriteLine("\nContains(\"Deinonychus\"): {0}",
            dinosaurs.Contains("Deinonychus"));

        Console.WriteLine("\nInsert(2, \"Compsognathus\")");
        dinosaurs.Insert(2, "Compsognathus");

        Console.WriteLine();
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        // Shows accessing the list using the Item property.
        Console.WriteLine("\ndinosaurs[3]: {0}", dinosaurs[3]);

        Console.WriteLine("\nRemove(\"Compsognathus\")");
        dinosaurs.Remove("Compsognathus");

        Console.WriteLine();
        foreach(string dinosaur in dinosaurs)
        {
            Console.WriteLine(dinosaur);
        }

        dinosaurs.TrimExcess();
        Console.WriteLine("\nTrimExcess()");
        Console.WriteLine("Capacity: {0}", dinosaurs.Capacity);
        Console.WriteLine("Count: {0}", dinosaurs.Count);

        dinosaurs.Clear();
        Console.WriteLine("\nClear()");
        Console.WriteLine("Capacity: {0}", dinosaurs.Capacity);
        Console.WriteLine("Count: {0}", dinosaurs.Count);
    }
}

/* This code example produces the following output:

Capacity: 0

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

Capacity: 8
Count: 5

Contains("Deinonychus"): True

Insert(2, "Compsognathus")

Tyrannosaurus
Amargasaurus
Compsognathus
Mamenchisaurus
Deinonychus
Compsognathus

dinosaurs[3]: Mamenchisaurus

Remove("Compsognathus")

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

TrimExcess()
Capacity: 5
Count: 5

Clear()
Capacity: 5
Count: 0
 */
Imports System
Imports System.Collections.Generic

Public Class Example

    Public Shared Sub Main()
        Dim dinosaurs As New List(Of String)

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)

        dinosaurs.Add("Tyrannosaurus")
        dinosaurs.Add("Amargasaurus")
        dinosaurs.Add("Mamenchisaurus")
        dinosaurs.Add("Deinonychus")
        dinosaurs.Add("Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        Console.WriteLine(vbLf & "Capacity: {0}", dinosaurs.Capacity)
        Console.WriteLine("Count: {0}", dinosaurs.Count)

        Console.WriteLine(vbLf & "Contains(""Deinonychus""): {0}", _
            dinosaurs.Contains("Deinonychus"))

        Console.WriteLine(vbLf & "Insert(2, ""Compsognathus"")")
        dinosaurs.Insert(2, "Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next
        ' Shows how to access the list using the Item property.
        Console.WriteLine(vbLf & "dinosaurs(3): {0}", dinosaurs(3))
        Console.WriteLine(vbLf & "Remove(""Compsognathus"")")
        dinosaurs.Remove("Compsognathus")

        Console.WriteLine()
        For Each dinosaur As String In dinosaurs
            Console.WriteLine(dinosaur)
        Next

        dinosaurs.TrimExcess()
        Console.WriteLine(vbLf & "TrimExcess()")
        Console.WriteLine("Capacity: {0}", dinosaurs.Capacity)
        Console.WriteLine("Count: {0}", dinosaurs.Count)

        dinosaurs.Clear()
        Console.WriteLine(vbLf & "Clear()")
        Console.WriteLine("Capacity: {0}", dinosaurs.Capacity)
        Console.WriteLine("Count: {0}", dinosaurs.Count)
    End Sub
End Class

' This code example produces the following output:
'
'Capacity: 0
'
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Deinonychus
'Compsognathus
'
'Capacity: 8
'Count: 5
'
'Contains("Deinonychus"): True
'
'Insert(2, "Compsognathus")
'
'Tyrannosaurus
'Amargasaurus
'Compsognathus
'Mamenchisaurus
'Deinonychus
'Compsognathus
'
'dinosaurs(3): Mamenchisaurus
'
'Remove("Compsognathus")
'
'Tyrannosaurus
'Amargasaurus
'Mamenchisaurus
'Deinonychus
'Compsognathus
'
'TrimExcess()
'Capacity: 5
'Count: 5
'
'Clear()
'Capacity: 5
'Count: 0
using namespace System;
using namespace System::Collections::Generic;

void main()
{
    List<String^>^ dinosaurs = gcnew List<String^>();

    Console::WriteLine("\nCapacity: {0}", dinosaurs->Capacity);

    dinosaurs->Add("Tyrannosaurus");
    dinosaurs->Add("Amargasaurus");
    dinosaurs->Add("Mamenchisaurus");
    dinosaurs->Add("Deinonychus");
    dinosaurs->Add("Compsognathus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\nCapacity: {0}", dinosaurs->Capacity);
    Console::WriteLine("Count: {0}", dinosaurs->Count);

    Console::WriteLine("\nContains(\"Deinonychus\"): {0}",
        dinosaurs->Contains("Deinonychus"));

    Console::WriteLine("\nInsert(2, \"Compsognathus\")");
    dinosaurs->Insert(2, "Compsognathus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    Console::WriteLine("\ndinosaurs[3]: {0}", dinosaurs[3]);

    Console::WriteLine("\nRemove(\"Compsognathus\")");
    dinosaurs->Remove("Compsognathus");

    Console::WriteLine();
    for each(String^ dinosaur in dinosaurs )
    {
        Console::WriteLine(dinosaur);
    }

    dinosaurs->TrimExcess();
    Console::WriteLine("\nTrimExcess()");
    Console::WriteLine("Capacity: {0}", dinosaurs->Capacity);
    Console::WriteLine("Count: {0}", dinosaurs->Count);

    dinosaurs->Clear();
    Console::WriteLine("\nClear()");
    Console::WriteLine("Capacity: {0}", dinosaurs->Capacity);
    Console::WriteLine("Count: {0}", dinosaurs->Count);
}

/* This code example produces the following output:

Capacity: 0

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

Capacity: 8
Count: 5

Contains("Deinonychus"): True

Insert(2, "Compsognathus")

Tyrannosaurus
Amargasaurus
Compsognathus
Mamenchisaurus
Deinonychus
Compsognathus

dinosaurs[3]: Mamenchisaurus

Remove("Compsognathus")

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

TrimExcess()
Capacity: 5
Count: 5

Clear()
Capacity: 5
Count: 0
 */

[<EntryPoint>]
let main argv = 
    // We refer to System.Collections.Generic.List<'T> by its type 
    // abbreviation ResizeArray<'T> to avoid conflict with the List module.    
    // Note: In F# code, F# linked lists are usually preferred over
    // ResizeArray<'T> when an extendable collection is required.
    let dinosaurs = ResizeArray<_>()

    // Write out the dinosaurs in the ResizeArray.
    let printDinosaurs() =
        printfn ""
        dinosaurs |> Seq.iter (fun p -> printfn "%O" p) 


    printfn "\nCapacity: %i" dinosaurs.Capacity

    dinosaurs.Add("Tyrannosaurus")
    dinosaurs.Add("Amargasaurus")
    dinosaurs.Add("Mamenchisaurus")
    dinosaurs.Add("Deinonychus")
    dinosaurs.Add("Compsognathus")

    printDinosaurs()

    printfn "\nCapacity: %i" dinosaurs.Capacity
    printfn "Count: %i" dinosaurs.Count

    printfn "\nContains(\"Deinonychus\"): %b" (dinosaurs.Contains("Deinonychus"))

    printfn "\nInsert(2, \"Compsognathus\")"
    dinosaurs.Insert(2, "Compsognathus")

    printDinosaurs()

    // Shows accessing the list using the Item property.
    printfn "\ndinosaurs[3]: %s" dinosaurs.[3]

    printfn "\nRemove(\"Compsognathus\")"
    dinosaurs.Remove("Compsognathus") |> ignore

    printDinosaurs()

    dinosaurs.TrimExcess()
    printfn "\nTrimExcess()"
    printfn "Capacity: %i" dinosaurs.Capacity
    printfn "Count: %i" dinosaurs.Count

    dinosaurs.Clear()
    printfn "\nClear()"
    printfn "Capacity: %i" dinosaurs.Capacity
    printfn "Count: %i" dinosaurs.Count

    0 // return an integer exit code

    (* This code example produces the following output:

Capacity: 0

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

Capacity: 8
Count: 5

Contains("Deinonychus"): true

Insert(2, "Compsognathus")

Tyrannosaurus
Amargasaurus
Compsognathus
Mamenchisaurus
Deinonychus
Compsognathus

dinosaurs[3]: Mamenchisaurus

Remove("Compsognathus")

Tyrannosaurus
Amargasaurus
Mamenchisaurus
Deinonychus
Compsognathus

TrimExcess()
Capacity: 5
Count: 5

Clear()
Capacity: 5
Count: 0
    *)
Version Information
Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Thread Safety

Public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

It is safe to perform multiple read operations on a List, but issues can occur if the collection is modified while it’s being read. To ensure thread safety, lock the collection during a read or write operation. To enable a collection to be accessed by multiple threads for reading and writing, you must implement your own synchronization. For collections with built-in synchronization, see the classes in the System.Collections.Concurrent namespace. For an inherently thread–safe alternative, see the ImmutableList class.

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