title: Telerik asp.net client side validation
body: <p>I want to client validate a form before postback so I'm using the onclientclick event to validate the form and if it's valid, do some server side stuff. </p>
  
  <p>here  my code:</p>
  
  <pre><code>&lt;head runat="server"&gt;
      &lt;script type="text/javascript" id="Script1"&gt;
          function performCheck() {
              return $("TextBox1").val() == "";
          }
  &lt;/script&gt;
      &lt;title&gt;&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;form id="form1" runat="server" &gt;
          &lt;telerik:RadScriptManager ID="RadScriptManager1" runat="server"&gt;
  
          &lt;/telerik:RadScriptManager&gt;
      &lt;div&gt;
              &lt;asp:TextBox ID="TextBox1" runat="server" CausesValidation="true" ValidationGroup="thisGpo"&gt;&lt;/asp:TextBox&gt;
          &lt;asp:RequiredFieldValidator EnableClientScript="true"  ID="RequiredFieldValidator1" ValidationGroup="thisGpo" runat="server" ControlToValidate="TextBox1" ErrorMessage="RequiredFieldValidator"&gt;&lt;/asp:RequiredFieldValidator&gt;
          &lt;asp:Button OnClientClick="performCheck()"  ID="Button1" runat="server" Text="Button" ValidationGroup="thisGpo" CausesValidation="true" /&gt;     &lt;/div&gt;
      &lt;/form&gt;
  &lt;/body&gt;
  </code></pre>
  
  <p>Problem is, if I use telerik controls,  they add the tag</p>
  
  <pre><code>    &lt;telerik:RadScriptManager ID="RadScriptManager1" runat="server"&gt;
  &lt;/telerik:RadScriptManager&gt;
  </code></pre>
  
  <p>and this thing form hell is causing postbacks overring my code, so it is frustrating.</p>
  
  <p>My boss force us to use of Telerik because they have this fancy numericTextbox and he is paying.</p>
  
  <p>Tried to contact TELERIK but they mentioned they can't give us support because our version has expired.</p>