I have a model class as follows:

namespace MvcApplication1.Models
{
    public enum Sex { Male, Female };
    public class Person
    {
        public int Id { get; set; }
        public string Name { get; set; }

        [Required(ErrorMessage="Please select either Female or Male.")]
        public Sex? Sex { get; set; }
    }
}

The Edit action does :

namespace MvcApplication1.Controllers
{
    public class HomeController : Controller
    {
        public ActionResult Edit()
        {
            var Person = new Person { Id = 1, Name = "Someone", Sex = Sex.Male };
            return View(Person);
        }
    }
}

Question 1

How to mark up the Edit view such that there is a dropdown control containing 3 options: "--Select--", "Female", and "Male". For the Person passed to the view, "Male" must be selected.

Question 2

How to make up the Create view and leave the dropdown control selec开发者_如何学Pythonting "--Select--" by default.

Here is the Create action:

 public ActionResult Create()
 {
       var Person = new Person();
       return View(Person);
 }

There is a good answer already on how to convert an Enum into a SelectList but I'll reuse that code inline to simply the answer.

public ActionResult Edit()
{
    var Person = new Person { Id = 1, Name = "Someone", Sex = Sex.Male };
    List<object> values = new List<object>();
    values.Add(new { ID = "choose", Name = "--Select--" });
    values.AddRange(from Sex sex in Enum.GetValues(typeof(Sex))
            select new { ID = sex, Name = sex.ToString() });            
    ViewData["sexes"] = new SelectList(values, "Id", "Name", Person.Sex);
    return View(Person);
}

Now the Edit.cshtml view:

@model Test.Models.Person

@{
    ViewBag.Title = "Edit";
    Layout = "~/Views/Shared/_Layout.cshtml";
}

<h2>Edit</h2>

<script src="@Url.Content("~/Scripts/jquery.validate.min.js")" type="text/javascript"></script>
<script src="@Url.Content("~/Scripts/jquery.validate.unobtrusive.min.js")" type="text/javascript"></script>

@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
    <fieldset>
        <legend>Person</legend>

        @Html.HiddenFor(model => model.Id)

        <div class="editor-label">
            @Html.LabelFor(model => model.Name)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Name)
            @Html.ValidationMessageFor(model => model.Name)
        </div>

        <div class="editor-label">
            @Html.LabelFor(model => model.Sex)
        </div>
        <div class="editor-field">            
            @Html.DropDownListFor(model => model.Sex, (SelectList)ViewData["sexes"])
            @Html.ValidationMessageFor(model => model.Sex)
        </div>

        <p>
            <input type="submit" value="Save" />
        </p>
    </fieldset>
}

<div>
    @Html.ActionLink("Back to List", "Index")
</div>

Now the control action to post the form to:

[HttpPost]
public ActionResult Edit(Person person)
{
    var newName = person.Name;
    var newSex = person.Sex;

    return RedirectToAction("index", "home");
}

Now run the project in debug mode with a break on the return RedirectToAction("index", "home"); line in the post-to Edit action. See how you can change form values in the view and then do what you need to do in the posted-to action? There are other options than using ViewData to pass the list but they complicate the example and are plentiful.

The Create action would look like this:

public ActionResult Create()
{
    Person person = new Person();
    List<object> values = new List<object>();
    values.Add(new { ID = "choose", Name = "--Select--" });
    values.AddRange(from Sex sex in Enum.GetValues(typeof(Sex))
            select new { ID = sex, Name = sex.ToString() });
    ViewData["sexes"] = new SelectList(values, "Id", "Name");
    return View(person);
}

The default select list item will be the first one so it would show "--Select--" as the default choice.