Question

I have page user creation and it contains textbox control. I want to restrict user entering html tag in i.e < and > sign in textbox using .net validation control.

Can any one help me about in this?

I also want to restrict double quote i.e ” and caret sign ^ can you please tell me how to write expression for that???

Answer 1

Use a regularexpressionvalidator…

<asp:textbox id="theTextbox" runat="server" />
<asp:regularexpressionvalidator id="regexValiator" runat="server"
    controltovalidate="theTextbox"
    errormessage='&lt;, &gt;, ", and ^ not allowed'
    display="Dynamic"
    validationexpression='([^<>\"\^])*' />

Actually, by default ASP.Net dissallow HTML content to be entered in form fields. No need for further validation.