EntityFrameworkQueryableExtensions.ContainsAsync<TSource> Method
Definition
Important
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Asynchronously determines whether a sequence contains a specified element by using the default equality comparer.
public static System.Threading.Tasks.Task<bool> ContainsAsync<TSource> (this System.Linq.IQueryable<TSource> source, TSource item, System.Threading.CancellationToken cancellationToken = default);static member ContainsAsync : System.Linq.IQueryable<'Source> * 'Source * System.Threading.CancellationToken -> System.Threading.Tasks.Task<bool><Extension()>
Public Function ContainsAsync(Of TSource) (source As IQueryable(Of TSource), item As TSource, Optional cancellationToken As CancellationToken = Nothing) As Task(Of Boolean)Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- IQueryable<TSource>
An IQueryable<T> to return the single element of.
- item
- TSource
The object to locate in the sequence.
- cancellationToken
- CancellationToken
A CancellationToken to observe while waiting for the task to complete.
Returns
A task that represents the asynchronous operation.
The task result contains true if the input sequence contains the specified value; otherwise,
false.
Exceptions
source is null.
If the CancellationToken is canceled.
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
Entity Framework