Hi,
I need to allow only alphanumeric characters and only comma and underscore to be entered in the textbox.
Could anyone please let me know how to do this.
Thanks!
Please refer this article
Regular Expression (Regex) to accept only Alphabets and Space in TextBox in ASP.Net
Change the ValidationExpression to
ValidationExpression="[a-zA-Z0-9,_]*$"
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ControlToValidate="TextBox1" ValidationExpression="[a-zA-Z0-9,_]*$" ErrorMessage="*Valid characters: Alphabets and Special Characters (,_)." />
