Cancelling an Asynchronous PostBack in ASP.NET Ajax

The behavior of an asynchronous PostBack is quite similar to a synchronous PostBack. In an asynchronous model, all the server side events occur, as they do in a synchronous model. The Microsoft AJAX Library also raises client side events. However when the page is rendered, asynchronous PostBack renders only the contents of the UpdatePanel, whereas in a synchronous PostBack, the entire page is recreated and sent back to the browser. In one of the previous articles, I had shown how to cancel a synchronous PostNack using ASP.NET. In this article, we will see how to cancel an asynchronous PostBack.

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