server side function is not fired while post back in jquery ui

There is a drop down list in the jquery ui modal form with id开发者_JS百科 - drpAction.When the selection is changed I need to execute drpAction_SelectedIndexChanged function in the code behind. When I just try to invoke the function like onSelectedImdexChanged="drpAction_SelectedIndexChanged" ,the function is not fired. How can I solve the problem?

Do you want a full postback, or an AJAX call? For full postback, add AutoPostBack="True" to your DropDownList. For an AJAX call, you should hook a JQuery event handler to the DropDownLists "onchange" event (remember that a DropDownlist is rendered as a SELECT tag)