Required+regular validation
<pre><code> &lt;asp:TextBox ID="Textboxtotalamount" 
     OnTextChanged="AmountChanged" 
     Width="90px" 
     AutoPostBack="true" 
     runat="server"&gt;&lt;/asp:TextBox&gt;

 &lt;asp:RequiredFieldValidator ID="RequiredFieldValidator" 
     runat="server" 
     ControlToValidate="Textboxtotalamount" 
     SetFocusOnError="True" 
     ValidationGroup="val"&gt;*&lt;/asp:RequiredFieldValidator&gt;

 &lt;asp:RegularExpressionValidator ID="RegularExpressionValidator1" 
     runat="server" 
     ControlToValidate="Textboxtotalamount" 
     ValidationExpression="^[-+]?[1-9]\d{0,13}(\.\d{1,3})?%?$" 
     SetFocusOnError="True"&gt;F&lt;/asp:RegularExpressionValidator&gt;
</code></pre>

<p>in this above code can validate correctly.......but in text box i  call "OnTextChanged"
event ....suppose if i type(characters)in textbox errormesge shown at the same time ontextchanged event also called hen error occured ....i ve to stop OnTextChanged event when regularexpression raised......
pls help</p>
