title: Not firing on server side onclick
body: <p>I had set validation for a button called <code>valsave()</code> at the end of the validation I disabled the button. </p>
  
  <p>Both validation and disabling function works properly, but server side onclick function for the same  button is not firing.</p>
  
  <pre><code>&lt;asp:Button ID="btnSave" runat="server" Text="Save" TabIndex="16" SkinID="imgsave"
  ToolTip="Save" OnClientClick="return valSave();" OnClick="btnSave_Click" /&gt;
  
   function valSave()
   {
  
  
  if(document.getElementById('hifMsgClick').value=='')
  {
      vtxtPRequestDate=document.getElementById('txtPRequestDate');
      vdgvPurReq=document.getElementById('dgvPurReq');        
  
      if(vtxtPRequestDate.value.length==0)
      {
          showMsgbox('BLANK','Purchase Request Date','2','txtPRequestDate'); 
          return false;
      }        
  
     if(vdgvPurReq == null)  
     {
          showMsgbox('BLANK','Purchase Request Details','2','ddlItemRequestID');               
          return false;
     }
  
  }    
  else
  {
      var vvalue=document.getElementById('hifMsgClick').value;   
      document.getElementById(vvalue).focus();
      document.getElementById('hifMsgClick').value="";
      return false;
  }
    var vbtnSave=document.getElementById('btnSave');
    vbtnSave.disabled = true;  
    vbtnSave.value = 'Pls..wait';   
    __doPostBack('btnSave','OnClick'); }
  </code></pre>
  
  <p>How can I make the server side onclick fire?</p>