How can I convert an enumeration into a List?

问题

i have an asp.net-mvc webpage and i want to show a dropdown list that is based off an enum. I want to show the text of each enum item and the id being the int value that the enum is associated with. Is there any elegant way of doing this conversion?

回答1:

You can use LINQ:

Enum.GetValues(typeof(MyEnum)).Cast<MyEnum>().Select(v => new SelectListItem {
    Text = v.ToString(),
    Value = ((int)v).ToString()
}).ToList();

回答2:

Since MVC 5.1, the most elegant way would be to use EnumDropDownListFor method of Html helper if you need to populate select options in your view:

@Html.EnumDropDownListFor(m => m.MyEnumProperty,new { @class="form-control"})

or GetSelectList method of EnumHelper in your controller:

var enumList = EnumHelper.GetSelectList(typeof (MyEnum));

回答3:

I did this using a static method that I could reuse.

public static IEnumerable<SelectListItem> EnumToSelectList<T>()
{
    return (Enum.GetValues(typeof(T)).Cast<T>().Select(
        e => new SelectListItem() { Text = e.ToString(), Value = e.ToString() })).ToList();
}

回答4:

You can use Enum.GetNames() to get a string array containing the names of the enum items. If your item names are user friendly, then this is probably good enough. Otherwise, you could create your own GetName() method that would return a nice name for each item.

OR - if the enum will never (or rarely) change, you could just create a method that directly adds hard-coded items to your dropdown. This is probably more efficient (if that is important to you).

回答5:

Now I used Tuple<string, string> but you can convert this to use anything:

var values = Enum.GetValues(typeof(DayOfWeek))
    .Cast<DayOfWeek>()
    .Select(d => Tuple.Create(((int)d).ToString(), d.ToString()))
    .ToList()

回答6:

I used GetEnumSelectList from the Html Helper class

<select asp-for="MyProperty" class="form-control" asp-items="@Html.GetEnumSelectList<MyEnum>()" ></select>

来源：https://stackoverflow.com/questions/3489453/how-can-i-convert-an-enumeration-into-a-listselectlistitem

标签

asp.net-mvc

enums

selectlistitem

How can I convert an enumeration into a List<SelectListItem>?