If you examine the ASP.NET AJAX JavaScript source code, you’ll see lots of “===” compare operators where you’d expect to find the normal “==” operator. Both will evaluate if an object is equal, but the “===” takes it another step further and validates that the objects being compared share the same identity. That means, in order for “===” to return true, the objects must be equal without JavaScript performing any data type conversions. This provides strict equality tests in JavaScript where loosely typed objects can often cause problems. And yes, “!==” exists, too. At this point we’ve sent our request to the server, received a response, and now we have an XML document object sitting in JavaScript memory. We’ve completed our asynchronous communication with the server, but now we need to update the page’s DOM. After all, the point of Ajax is to update the page without doing a full PostBack (and thus a full refresh) of the page. What should now be obvious is that
the harder part of creating an Ajax application is implementing the code that parses the server response and updates the page; the communication is actually fairly straight forward and easy.

Tags: Ajax security, Ajax-security, asp, asp-and-ajax