ASP.NET MVC 3 Remote Validation set custom error message

Question

Is there any way to set different errors according with logic in MVC 3.0 remote validation

public ActionResult IsUserEmailExists(string email)
        {
            bool isExists = service.IsUserExists(email);

            if(isExists )
             //Set error message
             return Json(!isExists, JsonRequestBehavior.AllowGet);
            else if(something)
              //another logic
              //Set errror message
              return Json(something, JsonRequestBehavior.AllowGet);             
        }

By default Remote validation using only ErrorMessage value from attribute declaration

[Remote("IsUserEmailExists", "Account", ErrorMessage = "User with such email already exists")]

is there any way to change that behavior?

Answer 1

You could return the error message instead of a boolean value:

return Json("Some custom error message", JsonRequestBehavior.AllowGet);

In this case the model will be considered invalid (the same as if you had returned false) and the string used as error message.