Question

Site will exclusively be used on mobile devices. So for fields requiring only numeric input, I want to bring up the numeric keypad. I can successfully do this by using an html input element with the type set to tel. I want to add an asp:RequiredFieldValidator to this field and based on MSDN.

I need to set the input to runat="server". When I do this, I get this error;

tel is not a valid type for an input tag.

If I remove the runat="server", I get

Unable to find control id Contract referenced by the ControlToValidate property of ''

Here is my code:

<input type="tel" runat="server" id="Contract"></input>
<asp:RequiredFieldValidator runat="server" ControlToValidate="Contract" 
                            ValidationGroup="IfOnRent" Text="*" 
                            ErrorMessage="Contract Required">
</asp:RequiredFieldValidator>

Am I just out of luck and have to code my own validations?

Answer 1

You may want to leave “type” undeclared in your code “front”. You can set this in the code behind (maybe in the Page_Init or Page_Load):

this.Contract.Attributes.Add("type", "tel");