Enumerable Class

Definition

Provides a set of static (Shared in Visual Basic) methods for querying objects that implement IEnumerable<T>.

public ref class Enumerable abstract sealed
public static class Enumerable
type Enumerable = class
Public Module Enumerable
Inheritance
Enumerable

Remarks

The methods in this class provide an implementation of the standard query operators for querying data sources that implement IEnumerable<T>. The standard query operators are general purpose methods that follow the LINQ pattern and enable you to express traversal, filter, and projection operations over data in any .NET-based programming language.

The majority of the methods in this class are defined as extension methods that extend IEnumerable<T>. This means they can be called like an instance method on any object that implements IEnumerable<T>.

Methods that are used in a query that returns a sequence of values do not consume the target data until the query object is enumerated. This is known as deferred execution. Methods that are used in a query that returns a singleton value execute and consume the target data immediately.

Methods

Aggregate<TSource,TAccumulate,TResult>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>, Func<TAccumulate,TResult>)

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.

Aggregate<TSource,TAccumulate>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>)

Applies an accumulator function over a sequence. The specified seed value is used as the initial accumulator value.

Aggregate<TSource>(IEnumerable<TSource>, Func<TSource,TSource,TSource>)

Applies an accumulator function over a sequence.

AggregateBy<TSource,TKey,TAccumulate>(IEnumerable<TSource>, Func<TSource, TKey>, Func<TKey,TAccumulate>, Func<TAccumulate,TSource,TAccumulate>, IEqualityComparer<TKey>)
AggregateBy<TSource,TKey,TAccumulate>(IEnumerable<TSource>, Func<TSource, TKey>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>, IEqualityComparer<TKey>)
All<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Determines whether all elements of a sequence satisfy a condition.

Any<TSource>(IEnumerable<TSource>)

Determines whether a sequence contains any elements.

Any<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Determines whether any element of a sequence satisfies a condition.

Append<TSource>(IEnumerable<TSource>, TSource)

Appends a value to the end of the sequence.

AsEnumerable<TSource>(IEnumerable<TSource>)

Returns the input typed as IEnumerable<T>.

Average(IEnumerable<Decimal>)

Computes the average of a sequence of Decimal values.

Average(IEnumerable<Double>)

Computes the average of a sequence of Double values.

Average(IEnumerable<Int32>)

Computes the average of a sequence of Int32 values.

Average(IEnumerable<Int64>)

Computes the average of a sequence of Int64 values.

Average(IEnumerable<Nullable<Decimal>>)

Computes the average of a sequence of nullable Decimal values.

Average(IEnumerable<Nullable<Double>>)

Computes the average of a sequence of nullable Double values.

Average(IEnumerable<Nullable<Int32>>)

Computes the average of a sequence of nullable Int32 values.

Average(IEnumerable<Nullable<Int64>>)

Computes the average of a sequence of nullable Int64 values.

Average(IEnumerable<Nullable<Single>>)

Computes the average of a sequence of nullable Single values.

Average(IEnumerable<Single>)

Computes the average of a sequence of Single values.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Computes the average of a sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Computes the average of a sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Computes the average of a sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Computes the average of a sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

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.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

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.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

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.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

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.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

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.

Average<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Computes the average of a sequence of Single values that are obtained by invoking a transform function on each element of the input sequence.

Cast<TResult>(IEnumerable)

Casts the elements of an IEnumerable to the specified type.

Chunk<TSource>(IEnumerable<TSource>, Int32)

Splits the elements of a sequence into chunks of size at most size.

Concat<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Concatenates two sequences.

Contains<TSource>(IEnumerable<TSource>, TSource)

Determines whether a sequence contains a specified element by using the default equality comparer.

Contains<TSource>(IEnumerable<TSource>, TSource, IEqualityComparer<TSource>)

Determines whether a sequence contains a specified element by using a specified IEqualityComparer<T>.

Count<TSource>(IEnumerable<TSource>)

Returns the number of elements in a sequence.

Count<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns a number that represents how many elements in the specified sequence satisfy a condition.

CountBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)
DefaultIfEmpty<TSource>(IEnumerable<TSource>)

Returns the elements of the specified sequence or the type parameter's default value in a singleton collection if the sequence is empty.

DefaultIfEmpty<TSource>(IEnumerable<TSource>, TSource)

Returns the elements of the specified sequence or the specified value in a singleton collection if the sequence is empty.

Distinct<TSource>(IEnumerable<TSource>)

Returns distinct elements from a sequence by using the default equality comparer to compare values.

Distinct<TSource>(IEnumerable<TSource>, IEqualityComparer<TSource>)

Returns distinct elements from a sequence by using a specified IEqualityComparer<T> to compare values.

DistinctBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Returns distinct elements from a sequence according to a specified key selector function.

DistinctBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Returns distinct elements from a sequence according to a specified key selector function and using a specified comparer to compare keys.

ElementAt<TSource>(IEnumerable<TSource>, Index)

Returns the element at a specified index in a sequence.

ElementAt<TSource>(IEnumerable<TSource>, Int32)

Returns the element at a specified index in a sequence.

ElementAtOrDefault<TSource>(IEnumerable<TSource>, Index)

Returns the element at a specified index in a sequence or a default value if the index is out of range.

ElementAtOrDefault<TSource>(IEnumerable<TSource>, Int32)

Returns the element at a specified index in a sequence or a default value if the index is out of range.

Empty<TResult>()

Returns an empty IEnumerable<T> that has the specified type argument.

Except<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Produces the set difference of two sequences by using the default equality comparer to compare values.

Except<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Produces the set difference of two sequences by using the specified IEqualityComparer<T> to compare values.

ExceptBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>)

Produces the set difference of two sequences according to a specified key selector function.

ExceptBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Produces the set difference of two sequences according to a specified key selector function.

First<TSource>(IEnumerable<TSource>)

Returns the first element of a sequence.

First<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the first element in a sequence that satisfies a specified condition.

FirstOrDefault<TSource>(IEnumerable<TSource>)

Returns the first element of a sequence, or a default value if the sequence contains no elements.

FirstOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the first element of the sequence that satisfies a condition or a default value if no such element is found.

FirstOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>, TSource)

Returns the first element of the sequence that satisfies a condition, or a specified default value if no such element is found.

FirstOrDefault<TSource>(IEnumerable<TSource>, TSource)

Returns the first element of a sequence, or a specified default value if the sequence contains no elements.

GroupBy<TSource,TKey,TElement,TResult>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>,TResult>)

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.

GroupBy<TSource,TKey,TElement,TResult>(IEnumerable<TSource>, Func<TSource, TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>, TResult>, IEqualityComparer<TKey>)

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.

GroupBy<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

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.

GroupBy<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

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.

GroupBy<TSource,TKey,TResult>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>)

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.

GroupBy<TSource,TKey,TResult>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>, IEqualityComparer<TKey>)

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.

GroupBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Groups the elements of a sequence according to a specified key selector function.

GroupBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Groups the elements of a sequence according to a specified key selector function and compares the keys by using a specified comparer.

GroupJoin<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,IEnumerable<TInner>, TResult>)

Correlates the elements of two sequences based on equality of keys and groups the results. The default equality comparer is used to compare keys.

GroupJoin<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,IEnumerable<TInner>, TResult>, IEqualityComparer<TKey>)

Correlates the elements of two sequences based on key equality and groups the results. A specified IEqualityComparer<T> is used to compare keys.

Index<TSource>(IEnumerable<TSource>)
Intersect<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Produces the set intersection of two sequences by using the default equality comparer to compare values.

Intersect<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values.

IntersectBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>)

Produces the set intersection of two sequences according to a specified key selector function.

IntersectBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TKey>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Produces the set intersection of two sequences according to a specified key selector function.

Join<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,TInner,TResult>)

Correlates the elements of two sequences based on matching keys. The default equality comparer is used to compare keys.

Join<TOuter,TInner,TKey,TResult>(IEnumerable<TOuter>, IEnumerable<TInner>, Func<TOuter,TKey>, Func<TInner,TKey>, Func<TOuter,TInner,TResult>, IEqualityComparer<TKey>)

Correlates the elements of two sequences based on matching keys. A specified IEqualityComparer<T> is used to compare keys.

Last<TSource>(IEnumerable<TSource>)

Returns the last element of a sequence.

Last<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the last element of a sequence that satisfies a specified condition.

LastOrDefault<TSource>(IEnumerable<TSource>)

Returns the last element of a sequence, or a default value if the sequence contains no elements.

LastOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the last element of a sequence that satisfies a condition or a default value if no such element is found.

LastOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>, TSource)

Returns the last element of a sequence that satisfies a condition, or a specified default value if no such element is found.

LastOrDefault<TSource>(IEnumerable<TSource>, TSource)

Returns the last element of a sequence, or a specified default value if the sequence contains no elements.

LongCount<TSource>(IEnumerable<TSource>)

Returns an Int64 that represents the total number of elements in a sequence.

LongCount<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns an Int64 that represents how many elements in a sequence satisfy a condition.

Max(IEnumerable<Decimal>)

Returns the maximum value in a sequence of Decimal values.

Max(IEnumerable<Double>)

Returns the maximum value in a sequence of Double values.

Max(IEnumerable<Int32>)

Returns the maximum value in a sequence of Int32 values.

Max(IEnumerable<Int64>)

Returns the maximum value in a sequence of Int64 values.

Max(IEnumerable<Nullable<Decimal>>)

Returns the maximum value in a sequence of nullable Decimal values.

Max(IEnumerable<Nullable<Double>>)

Returns the maximum value in a sequence of nullable Double values.

Max(IEnumerable<Nullable<Int32>>)

Returns the maximum value in a sequence of nullable Int32 values.

Max(IEnumerable<Nullable<Int64>>)

Returns the maximum value in a sequence of nullable Int64 values.

Max(IEnumerable<Nullable<Single>>)

Returns the maximum value in a sequence of nullable Single values.

Max(IEnumerable<Single>)

Returns the maximum value in a sequence of Single values.

Max<TSource,TResult>(IEnumerable<TSource>, Func<TSource,TResult>)

Invokes a transform function on each element of a generic sequence and returns the maximum resulting value.

Max<TSource>(IEnumerable<TSource>)

Returns the maximum value in a generic sequence.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Invokes a transform function on each element of a sequence and returns the maximum Decimal value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Invokes a transform function on each element of a sequence and returns the maximum Double value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Invokes a transform function on each element of a sequence and returns the maximum Int32 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Invokes a transform function on each element of a sequence and returns the maximum Int64 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Decimal value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Double value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Int32 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Int64 value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Invokes a transform function on each element of a sequence and returns the maximum nullable Single value.

Max<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Invokes a transform function on each element of a sequence and returns the maximum Single value.

Max<TSource>(IEnumerable<TSource>, IComparer<TSource>)

Returns the maximum value in a generic sequence.

MaxBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Returns the maximum value in a generic sequence according to a specified key selector function.

MaxBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Returns the maximum value in a generic sequence according to a specified key selector function and key comparer.

Min(IEnumerable<Decimal>)

Returns the minimum value in a sequence of Decimal values.

Min(IEnumerable<Double>)

Returns the minimum value in a sequence of Double values.

Min(IEnumerable<Int32>)

Returns the minimum value in a sequence of Int32 values.

Min(IEnumerable<Int64>)

Returns the minimum value in a sequence of Int64 values.

Min(IEnumerable<Nullable<Decimal>>)

Returns the minimum value in a sequence of nullable Decimal values.

Min(IEnumerable<Nullable<Double>>)

Returns the minimum value in a sequence of nullable Double values.

Min(IEnumerable<Nullable<Int32>>)

Returns the minimum value in a sequence of nullable Int32 values.

Min(IEnumerable<Nullable<Int64>>)

Returns the minimum value in a sequence of nullable Int64 values.

Min(IEnumerable<Nullable<Single>>)

Returns the minimum value in a sequence of nullable Single values.

Min(IEnumerable<Single>)

Returns the minimum value in a sequence of Single values.

Min<TSource,TResult>(IEnumerable<TSource>, Func<TSource,TResult>)

Invokes a transform function on each element of a generic sequence and returns the minimum resulting value.

Min<TSource>(IEnumerable<TSource>)

Returns the minimum value in a generic sequence.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Invokes a transform function on each element of a sequence and returns the minimum Decimal value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Invokes a transform function on each element of a sequence and returns the minimum Double value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Invokes a transform function on each element of a sequence and returns the minimum Int32 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Invokes a transform function on each element of a sequence and returns the minimum Int64 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Decimal value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Double value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Int32 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Int64 value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

Invokes a transform function on each element of a sequence and returns the minimum nullable Single value.

Min<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Invokes a transform function on each element of a sequence and returns the minimum Single value.

Min<TSource>(IEnumerable<TSource>, IComparer<TSource>)

Returns the minimum value in a generic sequence.

MinBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Returns the minimum value in a generic sequence according to a specified key selector function.

MinBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Returns the minimum value in a generic sequence according to a specified key selector function and key comparer.

OfType<TResult>(IEnumerable)

Filters the elements of an IEnumerable based on a specified type.

Order<T>(IEnumerable<T>)

Sorts the elements of a sequence in ascending order.

Order<T>(IEnumerable<T>, IComparer<T>)

Sorts the elements of a sequence in ascending order.

OrderBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Sorts the elements of a sequence in ascending order according to a key.

OrderBy<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Sorts the elements of a sequence in ascending order by using a specified comparer.

OrderByDescending<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Sorts the elements of a sequence in descending order according to a key.

OrderByDescending<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Sorts the elements of a sequence in descending order by using a specified comparer.

OrderDescending<T>(IEnumerable<T>)

Sorts the elements of a sequence in descending order.

OrderDescending<T>(IEnumerable<T>, IComparer<T>)

Sorts the elements of a sequence in descending order.

Prepend<TSource>(IEnumerable<TSource>, TSource)

Adds a value to the beginning of the sequence.

Range(Int32, Int32)

Generates a sequence of integral numbers within a specified range.

Repeat<TResult>(TResult, Int32)

Generates a sequence that contains one repeated value.

Reverse<TSource>(IEnumerable<TSource>)

Inverts the order of the elements in a sequence.

Select<TSource,TResult>(IEnumerable<TSource>, Func<TSource,Int32,TResult>)

Projects each element of a sequence into a new form by incorporating the element's index.

Select<TSource,TResult>(IEnumerable<TSource>, Func<TSource,TResult>)

Projects each element of a sequence into a new form.

SelectMany<TSource,TCollection,TResult>(IEnumerable<TSource>, Func<TSource,IEnumerable<TCollection>>, Func<TSource,TCollection,TResult>)

Projects each element of a sequence to an IEnumerable<T>, flattens the resulting sequences into one sequence, and invokes a result selector function on each element therein.

SelectMany<TSource,TCollection,TResult>(IEnumerable<TSource>, Func<TSource,Int32,IEnumerable<TCollection>>, Func<TSource,TCollection,TResult>)

Projects each element of a sequence to an IEnumerable<T>, 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.

SelectMany<TSource,TResult>(IEnumerable<TSource>, Func<TSource,IEnumerable<TResult>>)

Projects each element of a sequence to an IEnumerable<T> and flattens the resulting sequences into one sequence.

SelectMany<TSource,TResult>(IEnumerable<TSource>, Func<TSource,Int32,IEnumerable<TResult>>)

Projects each element of a sequence to an IEnumerable<T>, and flattens the resulting sequences into one sequence. The index of each source element is used in the projected form of that element.

SequenceEqual<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Determines whether two sequences are equal by comparing the elements by using the default equality comparer for their type.

SequenceEqual<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Determines whether two sequences are equal by comparing their elements by using a specified IEqualityComparer<T>.

Single<TSource>(IEnumerable<TSource>)

Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence.

Single<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.

SingleOrDefault<TSource>(IEnumerable<TSource>)

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.

SingleOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

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.

SingleOrDefault<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>, TSource)

Returns the only element of a sequence that satisfies a specified condition, or a specified default value if no such element exists; this method throws an exception if more than one element satisfies the condition.

SingleOrDefault<TSource>(IEnumerable<TSource>, TSource)

Returns the only element of a sequence, or a specified default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence.

Skip<TSource>(IEnumerable<TSource>, Int32)

Bypasses a specified number of elements in a sequence and then returns the remaining elements.

SkipLast<TSource>(IEnumerable<TSource>, Int32)

Returns a new enumerable collection that contains the elements from source with the last count elements of the source collection omitted.

SkipWhile<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Bypasses elements in a sequence as long as a specified condition is true and then returns the remaining elements.

SkipWhile<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>)

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.

Sum(IEnumerable<Decimal>)

Computes the sum of a sequence of Decimal values.

Sum(IEnumerable<Double>)

Computes the sum of a sequence of Double values.

Sum(IEnumerable<Int32>)

Computes the sum of a sequence of Int32 values.

Sum(IEnumerable<Int64>)

Computes the sum of a sequence of Int64 values.

Sum(IEnumerable<Nullable<Decimal>>)

Computes the sum of a sequence of nullable Decimal values.

Sum(IEnumerable<Nullable<Double>>)

Computes the sum of a sequence of nullable Double values.

Sum(IEnumerable<Nullable<Int32>>)

Computes the sum of a sequence of nullable Int32 values.

Sum(IEnumerable<Nullable<Int64>>)

Computes the sum of a sequence of nullable Int64 values.

Sum(IEnumerable<Nullable<Single>>)

Computes the sum of a sequence of nullable Single values.

Sum(IEnumerable<Single>)

Computes the sum of a sequence of Single values.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Decimal>)

Computes the sum of the sequence of Decimal values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Double>)

Computes the sum of the sequence of Double values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Int32>)

Computes the sum of the sequence of Int32 values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Int64>)

Computes the sum of the sequence of Int64 values that are obtained by invoking a transform function on each element of the input sequence.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Decimal>>)

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.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Double>>)

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.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int32>>)

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.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Int64>>)

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.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Nullable<Single>>)

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.

Sum<TSource>(IEnumerable<TSource>, Func<TSource,Single>)

Computes the sum of the sequence of Single values that are obtained by invoking a transform function on each element of the input sequence.

Take<TSource>(IEnumerable<TSource>, Int32)

Returns a specified number of contiguous elements from the start of a sequence.

Take<TSource>(IEnumerable<TSource>, Range)

Returns a specified range of contiguous elements from a sequence.

TakeLast<TSource>(IEnumerable<TSource>, Int32)

Returns a new enumerable collection that contains the last count elements from source.

TakeWhile<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Returns elements from a sequence as long as a specified condition is true.

TakeWhile<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>)

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.

ThenBy<TSource,TKey>(IOrderedEnumerable<TSource>, Func<TSource,TKey>)

Performs a subsequent ordering of the elements in a sequence in ascending order according to a key.

ThenBy<TSource,TKey>(IOrderedEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Performs a subsequent ordering of the elements in a sequence in ascending order by using a specified comparer.

ThenByDescending<TSource,TKey>(IOrderedEnumerable<TSource>, Func<TSource,TKey>)

Performs a subsequent ordering of the elements in a sequence in descending order, according to a key.

ThenByDescending<TSource,TKey>(IOrderedEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>)

Performs a subsequent ordering of the elements in a sequence in descending order by using a specified comparer.

ToArray<TSource>(IEnumerable<TSource>)

Creates an array from a IEnumerable<T>.

ToDictionary<TKey,TValue>(IEnumerable<KeyValuePair<TKey,TValue>>)

Creates a dictionary from an enumeration according to the default comparer for the key type.

ToDictionary<TKey,TValue>(IEnumerable<KeyValuePair<TKey,TValue>>, IEqualityComparer<TKey>)

Creates a dictionary from an enumeration according to specified key comparer.

ToDictionary<TKey,TValue>(IEnumerable<ValueTuple<TKey,TValue>>)

Creates a dictionary from an enumeration according to the default comparer for the key type.

ToDictionary<TKey,TValue>(IEnumerable<ValueTuple<TKey,TValue>>, IEqualityComparer<TKey>)

Creates a dictionary from an enumeration according to specified key equality comparer.

ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to specified key selector and element selector functions.

ToDictionary<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function, a comparer, and an element selector function.

ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function.

ToDictionary<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Creates a Dictionary<TKey,TValue> from an IEnumerable<T> according to a specified key selector function and key comparer.

ToHashSet<TSource>(IEnumerable<TSource>)

Creates a HashSet<T> from an IEnumerable<T>.

ToHashSet<TSource>(IEnumerable<TSource>, IEqualityComparer<TSource>)

Creates a HashSet<T> from an IEnumerable<T> using the comparer to compare keys.

ToList<TSource>(IEnumerable<TSource>)

Creates a List<T> from an IEnumerable<T>.

ToLookup<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to specified key selector and element selector functions.

ToLookup<TSource,TKey,TElement>(IEnumerable<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to a specified key selector function, a comparer and an element selector function.

ToLookup<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to a specified key selector function.

ToLookup<TSource,TKey>(IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Creates a Lookup<TKey,TElement> from an IEnumerable<T> according to a specified key selector function and key comparer.

TryGetNonEnumeratedCount<TSource>(IEnumerable<TSource>, Int32)

Attempts to determine the number of elements in a sequence without forcing an enumeration.

Union<TSource>(IEnumerable<TSource>, IEnumerable<TSource>)

Produces the set union of two sequences by using the default equality comparer.

Union<TSource>(IEnumerable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Produces the set union of two sequences by using a specified IEqualityComparer<T>.

UnionBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TSource>, Func<TSource,TKey>)

Produces the set union of two sequences according to a specified key selector function.

UnionBy<TSource,TKey>(IEnumerable<TSource>, IEnumerable<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Produces the set union of two sequences according to a specified key selector function.

Where<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>)

Filters a sequence of values based on a predicate.

Where<TSource>(IEnumerable<TSource>, Func<TSource,Int32,Boolean>)

Filters a sequence of values based on a predicate. Each element's index is used in the logic of the predicate function.

Zip<TFirst,TSecond,TResult>(IEnumerable<TFirst>, IEnumerable<TSecond>, Func<TFirst,TSecond,TResult>)

Applies a specified function to the corresponding elements of two sequences, producing a sequence of the results.

Zip<TFirst,TSecond,TThird>(IEnumerable<TFirst>, IEnumerable<TSecond>, IEnumerable<TThird>)

Produces a sequence of tuples with elements from the three specified sequences.

Zip<TFirst,TSecond>(IEnumerable<TFirst>, IEnumerable<TSecond>)

Produces a sequence of tuples with elements from the two specified sequences.

Applies to

See also