title: Telerik : preventing postback with RadButton confirm dialog
body: <p>I am having trouble to implement the confirm dialog to ask the user to confirm his choice to delete. The RadButton should not postback to the server if the user clicks cancel. The confirm dialog never shows, what am I doing wrong?</p>
  
  <pre><code>&lt;script type="text/javascript"&gt;
      function confirmAspButton(button) {
          function aspButtonCallbackFn(arg) {
              if (arg) {
                  __doPostBack(button.name, "");
              }
          }
          radconfirm("Are you sure you want to delete?", aspButtonCallbackFn, 330, 110, null, "Confirm");
      }
  &lt;/script&gt;
  
  
  &lt;telerik:RadButton
      ID="btnDeleteLines" 
      runat="server" 
      OnClientClicking="confirmAspButton(this); return false;"
      OnClick="btnDeleteLines_Click"
      Text="Delete line(s)"
      AutoPostBack="false"
      GroupName="GroupName1"&gt;
  &lt;/telerik:RadButton&gt;
  </code></pre>