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EntityFrameworkQueryableExtensions.ElementAtOrDefaultAsync<TSource> Method

Definition

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

public static System.Threading.Tasks.Task<TSource> ElementAtOrDefaultAsync<TSource> (this System.Linq.IQueryable<TSource> source, int index, System.Threading.CancellationToken cancellationToken = default);
static member ElementAtOrDefaultAsync : System.Linq.IQueryable<'Source> * int * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'Source>
<Extension()>
Public Function ElementAtOrDefaultAsync(Of TSource) (source As IQueryable(Of TSource), index As Integer, Optional cancellationToken As CancellationToken = Nothing) As Task(Of TSource)

Type Parameters

TSource

The type of the elements of source.

Parameters

source
IQueryable<TSource>

An IQueryable<T> to return the element from.

index
Int32

The zero-based index of the element to retrieve.

cancellationToken
CancellationToken

A CancellationToken to observe while waiting for the task to complete.

Returns

Task<TSource>

A task that represents the asynchronous operation. The task result contains the element at a specified index in a source sequence.

Exceptions

source is null.

Remarks

Multiple active operations on the same context instance are not supported. Use await to ensure that any asynchronous operations have completed before calling another method on this context. See Avoiding DbContext threading issues for more information and examples.

See Querying data with EF Core for more information and examples.

Applies to