IAsyncResult IController.BeginExecute(ActionInvocation action, AsyncCallback callback, object asyncState)
{
if (action == null) {
throw new ArgumentNullException("action");
}
if (callback == null) {
throw new ArgumentNullException("callback");
}
if (_asyncResult != null) {
throw new InvalidOperationException();
}
_action = action;
ActionDescriptor actionDescriptor = ControllerDescriptor.GetAction(this, action.ActionName);
if (actionDescriptor == null) {
throw new InvalidOperationException();
}
if (actionDescriptor.IsAsync) {
_asyncResult = new ActionAsyncResult(this, callback, asyncState);
try {
Task<ActionResult> task = (Task<ActionResult>)actionDescriptor.Invoke(this, action);
task.Completed += OnActionCompleted;
}
catch (Exception e) {
_asyncResult = new ActionAsyncResult(new ErrorActionResult(e), asyncState);
callback(_asyncResult);
}
}
else {
ActionResult result;
try {
result = (ActionResult)actionDescriptor.Invoke(this, action);
}
catch (Exception e) {
result = new ErrorActionResult(e);
}
_asyncResult = new ActionAsyncResult(result, asyncState);
callback(_asyncResult);
}
return _asyncResult;
}
