Enumerable.ElementAt<TSource> Method
Returns the element at a specified index in a sequence.
Namespace: System.Linq
Assembly: System.Core (in System.Core.dll)
Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- Type: System.Collections.Generic.IEnumerable<TSource>
An IEnumerable<T> to return an element from.
- index
- Type: System.Int32
The zero-based index of the element to retrieve.
Return Value
Type: TSourceThe element at the specified position in the source sequence.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerable<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).| Exception | Condition |
|---|---|
| ArgumentNullException | source is null. |
| ArgumentOutOfRangeException | index is less than 0 or greater than or equal to the number of elements in source. |
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<TSource> method.
The following code example demonstrates how to use ElementAt<TSource> 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'.
*/
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
