internal void Start(LegacyPageAsyncTaskManager manager, Object source, EventArgs args)
{
Debug.Assert(!_started);
_taskManager = manager;
_completionCallback = new AsyncCallback(this.OnAsyncTaskCompletion);
_started = true;
Debug.Trace("Async", "Start task");
try {
IAsyncResult ar = _beginHandler(source, args, _completionCallback, _state);
if (ar == null)
{
throw new InvalidOperationException(SR.GetString(SR.Async_null_asyncresult));
}
if (_asyncResult == null)
{
// _asyncResult could be not null if already completed
_asyncResult = ar;
}
}
catch (Exception e) {
Debug.Trace("Async", "Task failed to start");
_error = e;
_completed = true;
_completedSynchronously = true;
_taskManager.TaskCompleted(true /*onCallerThread*/); // notify TaskManager
// it is ok to say false (onCallerThread) above because this kind of
// error completion will never be the last in ResumeTasks()
}
}
internal void Start(LegacyPageAsyncTaskManager manager, Object source, EventArgs args) {
Debug.Assert(!_started);
_taskManager = manager;
_completionCallback = new AsyncCallback(this.OnAsyncTaskCompletion);
_started = true;
Debug.Trace("Async", "Start task");
try {
IAsyncResult ar = _beginHandler(source, args, _completionCallback, _state);
if (ar == null) {
throw new InvalidOperationException(SR.GetString(SR.Async_null_asyncresult));
}
if (_asyncResult == null) {
// _asyncResult could be not null if already completed
_asyncResult = ar;
}
}
catch (Exception e) {
Debug.Trace("Async", "Task failed to start");
_error = e;
_completed = true;
_completedSynchronously = true;
_taskManager.TaskCompleted(true /*onCallerThread*/); // notify TaskManager
// it is ok to say false (onCallerThread) above because this kind of
// error completion will never be the last in ResumeTasks()
}
}