Dopostback event coding if it doPostBack not available

<script type="text/javascript">

         //<![CDATA[

        

        

         function __doPostBack(eventTarget, eventArgument)

         {

             var theForm = document.getElementById("<%=form1.ClientID %>");

             if (!theForm.onsubmit || (theForm.onsubmit() != false))

             {

                 theForm.__EVENTTARGET.value = eventTarget;

                 theForm.__EVENTARGUMENT.value = eventArgument;

                 theForm.submit();

             }

         }

         //]]>

</script>

    <input type="hidden" name="__EVENTTARGET" id="__EVENTTARGET" value="" />

<input type="hidden" name="__EVENTARGUMENT" id="__EVENTARGUMENT" value="" />