Why can't I do like this?
[Required(ErrorMessage = "*")]
[RegularExpression("^[a-zA-Z0-9_]*$", ErrorMessage = Resources.RegistrationModel.UsernameError)]
public string Username { get; set; }
What is the error message telling me?
An attribute argument must be a constant expression , typeof expression or array creation expression of an attribute parameter type.
When you are using the ErrorMessage
property only constant strings or string literal can be assigned to it.
Use the ErrorMessageResourceType
and ErrorMessageResourceName
instead to specity your resources.
[RegularExpression(
"^[a-zA-Z0-9_]*$",
ErrorMessageResourceType=typeof(Resources.RegistrationModel),
ErrorMessageResourceName= "UsernameError"
)]
Note that the resources must be public (can be set in the resource editor).