FluentValidation always return generic error message

Question

I am using FluentValidation and I have the following validation rule:

      RuleFor(x => x.ClassId)
            .NotNull()
            .GreaterThan(0)
            .WithMessage("Class is required field");

but when ClassId is null it shows its generic error message:

'Class Id' must not be empty

How to show the error message I specified inside the WithMessage() method?

Answer 1

Depending on Md Farid Uddin Kiron's comment I think for every rule we need to add WithMessage() as followings:

      RuleFor(x => x.ClassId)
        .NotNull()
        .WithMessage("Class is required field")
        .GreaterThan(0)
        .WithMessage("Class is required field");