title: Yes No Cancel (3 buttons) for AJAX Modalpopupextender
body: <p>Does Ajax ModalPopupExtender has an option to create 3 buttons? Yes, No and Cancel? for ASP.NET WebForms, C#</p>
  
  <p>I could not come up with a solution. I can just find OKControlID and CancelControlID. </p>
  
  <p>
      
      
      </p>
  
  <pre><code>&lt;table id="pnlPopupMerchantUpdate" runat="server" style="display:none"&gt;
  &lt;tr&gt;
      &lt;td&gt;
          &lt;asp:Panel runat="server" CssClass="modalPopup"&gt;
              &lt;table width="350" height="80" class="warningPopup"&gt;
                  &lt;tr&gt;
                      &lt;td&gt;
                          &lt;!-- &lt;img src="images/warning_blue.gif" alt="Warning" /&gt; --&gt;
                      &lt;/td&gt;
                      &lt;td colspan="2" align="left" style="padding-left: 75px; padding-top: 10px;"&gt;
                          Do you wish to update the Location Information as well.
                      &lt;/td&gt;
                  &lt;/tr&gt;
                  &lt;tr&gt;
                      &lt;td align="center" colspan="4"&gt;
                          &lt;input id="btnYesMerchant" type="button" value="Yes" class="popupButton" causesvalidation="true" onclick="btnYessave_Click"/&gt; 
                          &lt;input id="btnNoMerchant" type="button" value="No" class="popupButton" causesvalidation="true" onclick="btnNosave_Click" /&gt; 
                          &lt;input id="btnCancel" type="button" value="Cancel" class="popupButton"/&gt;                            
                      &lt;/tr&gt;
              &lt;/table&gt;
          &lt;/asp:Panel&gt;
      &lt;/td&gt;
  &lt;/tr&gt;
  </code></pre>
  
  <p>Here, I do want to call different functions for Yes and No.</p>