I have a problem with the Required attribute in MVC. I have a field with a default value "Name". When I submit the form, MVC validates the field. If the field is empty, the required message appears. The problem is, that the error message do not appear because of the default value.
Is it possible, that the ErrorMessage also appears when the field has the default value "Name".
Sorry for my bad english :)
I will suggest two ways of dealing with this.
First, you can create a custom validation attribute, an example of which can be found [here].1
Here's a rough and ready example:
public class ValidateDefaultValueAttribute : ValidationAttribute {
protected override ValidationResult IsValid (object value, ValidationContext validationContext) {
string value = value.ToString();
if (value == "Name")
return new ValidationResult("Please enter a different name.");
return ValidationResult.Success;
}
}
Or, it sounds like you want to display a 'Name' in an input field? If you're using HTML 5 then try the placeholder attribute e.g.
<input type="text" placeholder="Name">
That will display the word 'Name' in the field but is overridden once the user starts typing in the field.
ValidateDefaultValueAttribute to receive the value (default name in this case) in the constructor ([ValidateDefaultValueAttribute(Value="Name")]), so it can be used in a more generic way for any field that rejects some default value.