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Enumerable.Last Method

Definition

Returns the last element of a sequence.

Overloads

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.

Last<TSource>(IEnumerable<TSource>)

Source:
Last.cs
Source:
Last.cs
Source:
Last.cs

Returns the last element of a sequence.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource Last(System::Collections::Generic::IEnumerable<TSource> ^ source);
public static TSource Last<TSource> (this System.Collections.Generic.IEnumerable<TSource> source);
static member Last : seq<'Source> -> 'Source
<Extension()>
Public Function Last(Of TSource) (source As IEnumerable(Of TSource)) As TSource

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IEnumerable<TSource>

An IEnumerable<T> to return the last element of.

Returns

TSource

The value at the last position in the source sequence.

Exceptions

source is null.

The source sequence is empty.

Examples

The following code example demonstrates how to use Last<TSource>(IEnumerable<TSource>) to return the last element of an array.

int[] numbers = { 9, 34, 65, 92, 87, 435, 3, 54,
                    83, 23, 87, 67, 12, 19 };

int last = numbers.Last();

Console.WriteLine(last);

/*
 This code produces the following output:

 19
*/
' Create an array of integers.
Dim numbers() As Integer =
{9, 34, 65, 92, 87, 435, 3, 54, 83, 23, 87, 67, 12, 19}

' Get the last item in the array.
Dim last As Integer = numbers.Last()

' Display the result.
Console.WriteLine(last)

' This code produces the following output:
'
' 19

Remarks

The Last<TSource>(IEnumerable<TSource>) method throws an exception if source contains no elements. To instead return a default value when the source sequence is empty, use the LastOrDefault method.

Applies to

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

Source:
Last.cs
Source:
Last.cs
Source:
Last.cs

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

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource Last(System::Collections::Generic::IEnumerable<TSource> ^ source, Func<TSource, bool> ^ predicate);
public static TSource Last<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,bool> predicate);
static member Last : seq<'Source> * Func<'Source, bool> -> 'Source
<Extension()>
Public Function Last(Of TSource) (source As IEnumerable(Of TSource), predicate As Func(Of TSource, Boolean)) As TSource

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IEnumerable<TSource>

An IEnumerable<T> to return an element from.

predicate
Func<TSource,Boolean>

A function to test each element for a condition.

Returns

TSource

The last element in the sequence that passes the test in the specified predicate function.

Exceptions

source or predicate is null.

No element satisfies the condition in predicate.

-or-

The source sequence is empty.

Examples

The following code example demonstrates how to use Last<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) to return the last element of an array that satisfies a condition.

int[] numbers = { 9, 34, 65, 92, 87, 435, 3, 54,
                    83, 23, 87, 67, 12, 19 };

int last = numbers.Last(num => num > 80);

Console.WriteLine(last);

/*
 This code produces the following output:

 87
*/
' Create an array of integers.
Dim numbers() As Integer =
{9, 34, 65, 92, 87, 435, 3, 54, 83, 23, 87, 67, 12, 19}

' Get the last element in the array whose value is
' greater than 80.
Dim last As Integer = numbers.Last(Function(num) num > 80)

' Display the result.
Console.WriteLine(last)

' This code produces the following output:
'
' 87

Remarks

The Last<TSource>(IEnumerable<TSource>, Func<TSource,Boolean>) method throws an exception if no matching element is found in source. To instead return a default value when no matching element is found, use the LastOrDefault method.

Applies to