Set Session variable and prevent postback on ASP.NET button click
<p>I have an ASP button that, when clicked, needs to set a session variable and run some javascript code to pop up a window.  I have this all working fine, however when this happens the main page does a postback and jumps back to the top of the page.  How can I prevent the postback and still set the session variable and call the javascript?  So that the main window stays in the same position?</p>
