Enumerable.ElementAt(IEnumerable<TSource>, Int32) Enumerable.ElementAt(IEnumerable<TSource>, Int32) Enumerable.ElementAt(IEnumerable<TSource>, Int32) Method

Definition

Returns the element at a specified index in a sequence.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static TSource ElementAt(System::Collections::Generic::IEnumerable<TSource> ^ source, int index);
public static TSource ElementAt<TSource> (this System.Collections.Generic.IEnumerable<TSource> source, int index);
<Extension()>
Public Function ElementAt(Of TSource) (source As IEnumerable(Of TSource), index As Integer) As TSource
Type Parameters
TSource

The type of the elements of source.

Parameters
source
IEnumerable<TSource>

An IEnumerable<T> to return an element from.

index
Int32 Int32 Int32

The zero-based index of the element to retrieve.

Returns

The element at the specified position in the source sequence.

Exceptions

index is less than 0 or greater than or equal to the number of elements in source.

Examples

The following code example demonstrates how to use ElementAt to return an element at a specific position.

string[] names =
    { "Hartono, Tommy", "Adams, Terry", "Andersen, Henriette Thaulow", 
        
        "Hedlund, Magnus", "Ito, Shu" };
Random random = new Random(DateTime.Now.Millisecond);

string name = names.ElementAt(random.Next(0, names.Length));

Console.WriteLine("The name chosen at random is '{0}'.", name);

/*
 This code produces the following sample output:

 The name chosen at random is 'Ito, Shu'.
*/

' Create an array of strings.
Dim names() As String =
{"Hartono, Tommy", "Adams, Terry", "Andersen, Henriette Thaulow", "Hedlund, Magnus", "Ito, Shu"}

Dim random As Random = New Random(DateTime.Now.Millisecond)

' Get a string at a random index within the array.
Dim name As String = names.ElementAt(random.Next(0, names.Length))

' Display the output.
MsgBox("The name chosen at random is " & name)

' This code produces the following output:
'
' The name chosen at random is Ito, Shu

Remarks

If the type of source implements IList<T>, that implementation is used to obtain the element at the specified index. Otherwise, this method obtains the specified element.

This method throws an exception if index is out of range. To instead return a default value when the specified index is out of range, use the ElementAtOrDefault method.

Applies to