difference between postback and asynchronous postback triggers

Asynchronous Postback triggers update the page partially without refreshing the whole page (AJAX)
Postback triggers update the complete page caused by complete post of the page to the server.

Hope this will help you understand these two concepts usually used in AJAX.

Regards,
Sheo Narayan
http://www.dotnetfunda.com

Laghaterohan, if this helps please login to Mark As Answer. | Alert Moderator

ok cool...so how does if affect if i have a button placed inside a update panel?
Apparently i have a gridview and a button both of them are placed inside a update panel with no triggers..The button is basically for exporting the gridview containts in xls format....but i got error on click on the button.
When i added a post back trigger it works fine....why is this so?

Thanks!

Best Regards,
Rohan Laghate

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Hi

By default when no triggers are defined for a control placed in a updatepanel that does postback is an Asynchronous Postback where page is rendered partially and script manager handles it, In your case i think you are writing your file to response object and ending the response, so header content has been modified which is invalid for scriptmanager.

Thanks,
Debata

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