title: RequiredFieldValidator and OnClientClick Together
body: <p>I have one textbox (Mandatory using RequiredFieldValidator) and one submit button. I have applied an loading gif using the following code on button's <code>OnClientClick</code>.</p>
  
  <pre><code>&lt;asp:Image ID="ImgAjaxloaderClarification" ImageUrl="/images/ajaxloadernew.gif"
      AlternateText="Loading Image" runat="server"/&gt;                                            
  &lt;asp:ImageButton ID="btnRequestClarification" runat="server" 
     ImageUrl="/images/btn_RequestFutureClarif.png" ValidationGroup="VGFillHours"
      OnClientClick="return showContent();"                    
      OnClick="btnRequestClarification_Click" /&gt;
  </code></pre>
  
  <p>Following is the javascript function to show the loader gif. (Initially the gif set as display:'none')  </p>
  
  <pre><code>&lt;script type="text/javascript" language="javascript"&gt;
      function showContent() 
      {
          if (document.getElementById("&lt;%=RequiredFieldValidator1.ClientID %&gt;").getAttribute("IsValid")) 
          {
              document.getElementById("&lt;%=ImgAjaxloaderClarification.ClientID %&gt;").style.display = "block";
              return true;
          }
          return false;
      }
  &lt;/script&gt;
  </code></pre>
  
  <p>The issue is RequiredFieldValidator was working fine before calling the OnClientClick function. But it has suddenly stoped working. Allthough the gif is shown but the RequiredFieldValidator is not working.</p>
  
  <p>Any help.</p>