What is the difference between PostBack & Callback? Please give sample code?

[qwedster]

Folks!

What is the difference between PostBack and Callback ( !IsPostBack and if(!IsCallback) )

Like in the following Code Snippet:

        protected void Page_Load(object sender, EventArgs e)
        {           
            if (!IsPostBack)
            {

            }

            if(!IsCallback)
            {

            }
        }

As far as I know, when I 1) refresh the page or 2) revert back to the page after round trip, the behavior is such that IsPostBack = !IsCallback. I don't find any difference.

Can you please explain with example code?

Just want a sample code (for Page_Load event) that will demonstrate the difference in the Page_Load event so that I can toggle breakpoint and understand it for myself.

Thanks.

[PRR]

A Postback occurs when the data (the whole page) on the page is posted from the client to the server.During a page postback, the Web page and controls are recreated and a new version of the entire Web page is rendered on the client.

Callback is also a special kind of postback, but it is just a quick round-trip to the server to get a small set of data.
Link

Determine How ASP.NET Web Pages Were Invoked
Page.IsPostBack
Page.IsCallback

[qwedster]

Thanks for the reply!