DbRawSqlQuery<TElement>::FirstAsync Method
Asynchronously returns the first element of the query.
Assembly: EntityFramework (in EntityFramework.dll)
| Name | Description | |
|---|---|---|
![]() | FirstAsync() | Asynchronously returns the first element of the query. |
![]() | FirstAsync(CancellationToken) | Asynchronously returns the first element of the query. |
![]() | FirstAsync(Func<TElement, Boolean>^) | Asynchronously returns the first element of the query that satisfies a specified condition. |
![]() | FirstAsync(Func<TElement, Boolean>^, CancellationToken) | Asynchronously returns the first element of the query that satisfies a specified condition. |
DbRawSqlQuery<TElement>::FirstAsync Method ()
Asynchronously returns the first element of the query.
| Exception | Condition |
|---|---|
| InvalidOperationException | The query result is empty. |
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.
DbRawSqlQuery<TElement>::FirstAsync Method (CancellationToken)
Asynchronously returns the first element of the query.
Parameters
- cancellationToken
-
Type:
System.Threading::CancellationToken
A CancellationToken to observe while waiting for the task to complete.
Return Value
Type: System.Threading.Tasks::Task<TElement>^A task that represents the asynchronous operation. The task result contains the first element in the query result.
| Exception | Condition |
|---|---|
| InvalidOperationException | The query result is empty. |
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.
DbRawSqlQuery<TElement>::FirstAsync Method (Func<TElement, Boolean>^)
Asynchronously returns the first element of the query that satisfies a specified condition.
Parameters
- predicate
-
Type:
System::Func<TElement, Boolean>^
A function to test each element for a condition.
Return Value
Type: System.Threading.Tasks::Task<TElement>^A task that represents the asynchronous operation. The task result contains the first element in the query result that satisfies a specified condition.
| Exception | Condition |
|---|---|
| ArgumentNullException | predicate is null . |
| InvalidOperationException | The query result is empty. |
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.
DbRawSqlQuery<TElement>::FirstAsync Method (Func<TElement, Boolean>^, CancellationToken)
Asynchronously returns the first element of the query that satisfies a specified condition.
public: Task<TElement>^ FirstAsync( Func<TElement, bool>^ predicate, CancellationToken cancellationToken )
Parameters
- predicate
-
Type:
System::Func<TElement, Boolean>^
A function to test each element for a condition.
- cancellationToken
-
Type:
System.Threading::CancellationToken
A CancellationToken to observe while waiting for the task to complete.
Return Value
Type: System.Threading.Tasks::Task<TElement>^A task that represents the asynchronous operation. The task result contains the first element in the query result that satisfies a specified condition.
| Exception | Condition |
|---|---|
| ArgumentNullException | predicate is null . |
| InvalidOperationException | The query result is empty. |
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.
