Nested Where(x => x.Condition = value, () => {}); fluentvalidation

Question

Current project:

• ASP.NET 4.5.1
• MVC 5

I need to know if I can nest When() statements like this:

When(x => x.Cond1 == val1,
  () => {
    When(x => x.SubCond1 == SubVal1,
      () => {
        When(x => x.Final1 == finalVal1,
          () => {
            RuleFor(x => x.Field1)
              .NotEmpty().WithMessage("Should not be empty");
            // a few more here
          });
        When(x => x.Final2 == finalVal2,
          () => {
            RuleFor(x => x.Field8)
              .NotEmpty().WithMessage("Should not be empty");
            // a few more here
          });
      });
    When(x => x.SubCond2 == SubVal2,
      () => {
        RuleFor(x => x.Field16)
          .NotEmpty().WithMessage("Should not be empty");
        // a few more here
      });
  });

Because the last thing I want is to decorate 30+ form fields like this:

RuleFor(x => x.Field1)
  .NotEmpty().WithMessage("Should not be empty")
  .When(x => x.Cond1 == val)
  .When(x => x.SubCond1 == SubVal1)
  .When(x => x.Final1 == finalVal1);

That is just untenable.

None of the conditions require validation themselves, as none of them are actually user-editable fields (just user-selectable values); I just need to compare them against known values. I would use an if/else statement if that was actually more appropriate, which it isn’t.

The model is largely flat, with only the second-level When() representing an imported model, and the third-level being different ways to handle specific fields within the imported model.

Answer 1

You can't, but you can try and use Rule Sets to group your rules together. Also maybe check Cascade Mode.