自定义枚举作为可选参数

Question

  public enum Employee
    {
        FT,
        PT,
    }

This doesn't work

  public ActionResult Index(Employee s = Employee.PT)
        {
            ViewData["Message"] = s.ToString();

            return View("MyView");
        }

Exception Details: System.ArgumentException: The parameters dictionary contains an invalid entry for parameter 's' for method 'System.Web.Mvc.ActionResult Index(SampleControllerEx.Controllers.Employee)' in 'SampleControllerEx.Controllers.HomeController'. The dictionary contains a value of type 'System.Int32', but the parameter requires a value of type 'SampleControllerEx.Controllers.Employee'. Parameter name: parameters

But below one works,

public ActionResult Index([DefaultValue(Employee.PT)] Employee s)
        {
            ViewData["Message"] = s.ToString();

            return View("MyView");
        }

May I know why 'DefaultValue' only supports custom enum, where optional parameter(4.0) doesn't support it?

Answer 1

You can do it in such way:

 public ActionResult Index(int employeeType)
        {
            Employee s = (Employee) employeeType;
            ViewData["Message"] = s.ToString();

            return View("MyView");
        }