ReadAsync(CancellationToken) Method
In This Topic
This is the asynchronous version of System.Data.Common.DbDataReader.Read. Providers should override with an appropriate implementation. The cancellationToken may optionally be ignored. The default implementation invokes the synchronous System.Data.Common.DbDataReader.Read method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellationToken. Exceptions thrown by Read will be communicated via the returned Task Exception property. Do not invoke other methods and properties of the DbDataReader object until the returned Task is complete. Advances the reader to the next record in a result set.
Syntax
'Declaration
<System.Runtime.CompilerServices.AsyncStateMachineAttribute(VistaDB.Provider.VistaDBDataReader/d__70)>
Public Overloads Overrides NotOverridable Function ReadAsync( _
ByVal As System.Threading.CancellationToken _
) As System.Threading.Tasks.Task(Of Boolean)
'Usage
Dim instance As VistaDBDataReader
Dim cancellationToken As System.Threading.CancellationToken
Dim value As System.Threading.Tasks.Task(Of Boolean)
value = instance.ReadAsync(cancellationToken)
[System.Runtime.CompilerServices.AsyncStateMachine(VistaDB.Provider.VistaDBDataReader/d__70)]
public override System.Threading.Tasks.Task<bool> ReadAsync(
System.Threading.CancellationToken
)
Parameters
- cancellationToken
- The cancellation instruction.
Return Value
A task representing the asynchronous operation.
Exceptions
| Exception | Description |
| System.Data.Common.DbException | An error occurred while executing the command text. |
Example
See
VistaDBDataReader Class for an example of how to use this method.
Requirements
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
See Also