DbDataReader.ReadAsync Method

Definition

Asynchronously advances the reader to the next record in a result set.

Overloads

ReadAsync()

Asynchronously advances the reader to the next record in a result set.

ReadAsync(CancellationToken)

Asynchronously advances the reader to the next record in a result set.

Remarks

For more information about asynchronous programming, see Asynchronous Programming.

ReadAsync()

Asynchronously advances the reader to the next record in a result set.

public:
 System::Threading::Tasks::Task<bool> ^ ReadAsync();
public System.Threading.Tasks.Task<bool> ReadAsync ();
member this.ReadAsync : unit -> System.Threading.Tasks.Task<bool>
Public Function ReadAsync () As Task(Of Boolean)

Returns

A Task<TResult> whose Result property is true if there are more rows or false if there aren't.

Exceptions

An error occurred while executing the command text.

Remarks

The default implementation of this asynchronous method invokes its synchronous counterpart and returns a completed Task, potentially blocking the calling thread.

Data providers that support asynchronous programming should override the default implementation using asynchronous I/O operations.

Other methods and properties of the DbDataReader object should not be invoked while the returned Task is not yet completed.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such as ArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown by Read().

See also

Applies to

ReadAsync(CancellationToken)

Asynchronously advances the reader to the next record in a result set.

public:
 virtual System::Threading::Tasks::Task<bool> ^ ReadAsync(System::Threading::CancellationToken cancellationToken);
public virtual System.Threading.Tasks.Task<bool> ReadAsync (System.Threading.CancellationToken cancellationToken);
abstract member ReadAsync : System.Threading.CancellationToken -> System.Threading.Tasks.Task<bool>
override this.ReadAsync : System.Threading.CancellationToken -> System.Threading.Tasks.Task<bool>
Public Overridable Function ReadAsync (cancellationToken As CancellationToken) As Task(Of Boolean)

Parameters

cancellationToken
CancellationToken

The cancellation instruction.

Returns

A Task<TResult> whose Result property is true if there are more rows or false if there aren't.

Exceptions

An error occurred while executing the command text.

The cancellation token was canceled. This exception is stored into the returned task.

Remarks

The default implementation of this asynchronous method invokes its synchronous counterpart and returns a completed Task, potentially blocking the calling thread. The default implementation also returns a cancelled task if passed an already cancelled cancellation token.

Data providers that support asynchronous programming should override the default implementation using asynchronous I/O operations.

This method accepts a cancellation token that can be used to request the operation to be cancelled early. Implementations may ignore this request.

Other methods and properties of the DbDataReader object should not be invoked while the returned Task is not yet completed.

This method stores in the task it returns all non-usage exceptions that the method's synchronous counterpart can throw. If an exception is stored into the returned task, that exception will be thrown when the task is awaited. Usage exceptions, such as ArgumentException, are still thrown synchronously. For the stored exceptions, see the exceptions thrown by Read().

See also

Applies to