c# - asp.net button works once and then stops working -

i have imagefield works once first time displays messagebox when close messagebox using cancel button , here how

<script type="text/javascript">  $(document).ready(function() {    $('#<%= imagebutton1.clientid %>').click(function() {         alert('hello');  // works once          $.blockui({message: $('#maininsert')});      });   $('#<%= button2.clientid %>').click(function() {          $.unblockui();      }); });  </script> 

here how definsedh image button

<br /> <asp:imagebutton id="imagebutton1" runat="server" imagealign="right" imageurl="/_layouts/n.png" /> <br /> <br /> 

here's cancel button code,

 <div id="maininsert" style="display: none; cursor: default">     <asp:button id="button2" text="cancel" runat="server" cssclass="rightbutton" /> </div> 

you may bubbling through other events. sure stop propogation through click events of parents , children.

<script type="text/javascript">  $(document).ready(function() {    $('#<%= imagebutton1.clientid %>').click(function(event) {         alert('hello');  // works once          $.blockui({message: $('#maininsert')});          event.stoppropagation();     });   $('#<%= button2.clientid %>').click(function(event) {          $.unblockui();          event.stoppropagation();     }); });  </script> 

i not solve it, seems first shot.

joey