RegisterAsyncTask is an alternative way to execute task asynchronously in Asp.Net page.RegisterAsyncTask is an API that is,to some exten,independent from asynchronous pages.In fact, it also work when the Async attributes of the @Page directive is set to false.Combined with asynchronous pages,though,it forms an extemely powerful programming model for lengthly operations.
You can use RegisterAsyncTask to register one or more asynchronous tasks.Tasks start when the page reach the async point- that is, immediately after the preRender event.
void Page_Load(object sender,EventArgs e)
{
PageAsyncTask task = new PageAsyncTask (new BeginEventHandler(BeginTask),new EndEventHadler(EndTask),null,null);
RegisterAsyncTask(task);
}
To call RegisterAsyncTask, you need to first create an instance of the PageAsyncTask class.The Constructor accepts up to five parameters
PageAsyncTask let you specify a timeout function and an optional flag to enable multiple registered tasks to execute in parallel.
The timeout delegate indicate the method that will get called if the task is not completed within the aysnchronous timeout interval.By default,an asynchronous task time out if not completed within 45 seconds.You can indicate a different timeout in either the configuration file or the @Page directive.Here's what you need if you opt for the web.config file
The @Page directive contains an integer AsynTimeout attribute that you set to the desire number of seconds.
