Question

here’s my function for checking zipcode. When a null values comes in, i keep getting “Object Required” Does anyone know where im going wrong?

aspx tags –

asp:CustomValidator 
    ID="cv_zipcode" 
    runat="server"      
    ControlToValidate="tb_zipcode"
    ClientValidationFunction="ValidateZipcode" 
    ValidateEmptyText="true" 
    Display="Dynamic" 
    ValidationGroup="vgroup">
</asp:CustomValidator>

 

function ValidateZipcode(sender, args) {
              var regZipcode = '\d{5}'
        var zipcode = document.getElementById(sender.id.replace(/cv_/, "tb_"));
                    if ((zipcode.value == "ZipCode") || (zipcode.value.length == null) || (zipcode.value.length == "")) {
            zipcode.style.backgroundColor = "#f6e086";
            args.IsValid = false; return;
        } else {
            args.IsValid = true;
            zipcode.style.backgroundColor = "white";
        }
    }

Answer 1

I’m not sure exactly which value is null, but in general, if you have a variable x which may or may not be null, and you want to do something with x, you can do the following:

x != null && do_something_with(x)

If x == null, then this returns false and doesn’t try to execute do_something_with(). Otherwise, this expression returns the value of do_something_with(x).

If you just do_something_with(x), and x is null, and do_something_with() is not expecting a null, you can get errors.

EDIT:

try:

if ((zipcode == null) || (zipcode.value == null) || [everything else])