ISSAsynchStatus::WaitForAsynchCompletion (OLE DB)
Waits until the asynchronously executing operation is complete or until a time-out occurs.
구문
HRESULT WaitForAsynchCompletion(
DWORD dwMillisecTimeOut);
Arguments
- dwMillisecTimeOut[in]
Time-out in milliseconds.
Return Code Values
- S_OK
The method succeeded.
- E_UNEXPECTED
A rowset is in an unused state because ITransaction::Commit or ITransaction::Abort has been called or the rowset was cancelled during its initialization phase.
- DB_E_CANCELED
Asynchronous processing was cancelled during rowset population or data source object initialization.
- DB_S_ASYNCHRONOUS
The operation has not yet completed even though specified time-out has been reached.
[!참고] In addition to the return code values listed above, the ISSAsynchStatus::WaitForAsynchCompletion method also supports the return code values returned by the core OLEDB ICommand::Execute and IDBInitialize::Initialize methods.
주의
The ISSAsynchStatus::WaitForAsynchCompletion method will not return until the time-out value (in milliseconds) has passed or the pending operation is done. The Command object has a CommandTimeout property that controls the number of seconds a query will run before timing out. The CommandTimeout property will be ignored if used in conjunction with ISSAsynchStatus::WaitForAsynchCompletion method.
The time-out property is ignored for asynchronous operations. The time-out parameter of ISSAsynchStatus::WaitForAsynchCompletion specifies the maximum amount of time that will elapse before control is returned to the caller. If this time-out expires, DB_S_ASYNCHRONOUS will be returned. Time-outs never cancel asynchronous operations. If the application needs to cancel an asynchronous operation that does not complete within a time-out period, it must wait for the time-out and then explicitly cancel the operation if DB_S_ASYNCHRONOUS is returned.
[!참고] When the OLE DB Service Components are used, S_OK may be returned when DB_S_ASYNCHRONOUS is expected, so applications should call ISSAsynchStatus::GetStatus to check for completion when S_OK or DB_S_ASYNCHRONOUS is returned.
If the dwMillisecTimeOut value is set to INFINITE, the ISSAsynchStatus::WaitForAsynchCompletion method blocks until the operation is done. If the dwMillisecTimeOut value is set to 0, then the method will return immediately with the status of the pending operation. If the time-out expires before the operation is complete DB_S_ASYNCHRONOUS will be returned.
If the operation completes before the time-out expires, the returned HRESULT will be the HRESULT returned by the operation (the HRESULT that would have been returned had the operation been performed synchronously).
In addition, the SSPROP_ISSAsynchStatus property has been added to the DBPROPSET_SQLSERVERROWSET property set. Providers that support the ISSAsynchStatus interface must implement this property with a value of VARIANT_TRUE.
참고 항목
참조
개념
Performing Asynchronous Operations