在MVC中级联所需的下拉菜单

Question

Any idea on how to implement 2 Required cascading dropdowns in ASP.Net MVC? I am stressin on the attribute [Required] because I already created the cascading dropdowns. My issue is, the child dropdown should show depending on certain values of the parent dropdown. But since both are decorated with the Required attribute, in case the child dropdown is not shown, the form does not submit. which is normal since both dropdowns are part of the form. How can I implement both dropdowns to be required but only if the child is visible on the form? is JavaScript the only way to do it? Thanks

Answer 1

Assuming you are using jQuery Validation Plugin, required only if #other is selected:

$("#myform").validate({
  rules: {
    dropdown1: {
      required: true
    },
    dropdown2: {
      required: function(element) {
        return $("#dropdown1").val() != "";
      }
    }
  }
});