使用下拉列表绑定枚举并在MVC C中的get动作中设置选定值＃

我有一个叫做CityType的Enum

 public enum CityType { [Description("Select City")] Select = 0, [Description("A")] NewDelhi = 1, [Description("B")] Mumbai = 2, [Description("C")] Bangalore = 3, [Description("D")] Buxar = 4, [Description("E")] Jabalpur = 5 } 

从枚举生成列表

 IList list = Enum.GetValues(typeof(CityType)).Cast().Select(x => new SelectListItem(){ Text = EnumHelper.GetDescription(x), Value = ((int)x).ToString() }).ToList(); int city=0; if (userModel.HomeCity != null) city= (int)userModel.HomeCity; ViewData["HomeCity"] = new SelectList(list, "Value", "Text", city); 

绑定.cshtml

 @Html.DropDownList("HomeCity",null,new { @style = "width:155px;", @class = "form-control" }) 

EnumHelper GetDescription类获取Enum的描述

Answer 1

我在博客上写了这个主题，我创建了一个EnumHelper来帮助完成这项常见任务。

http://jnye.co/Posts/4/creating-a-dropdown-list-from-an-enum-in-mvc-and-c%23

在你的控制器中：

 //If you don't have an enum value use the type ViewBag.DropDownList = EnumHelper.SelectListFor(); //If you do have an enum value use the value (the value will be marked as selected) ViewBag.DropDownList = EnumHelper.SelectListFor(MyEnum.MyEnumValue); 

在您的视图中：

 @Html.DropDownList("DropDownList") @* OR *@ @Html.DropDownListFor(m => m.Property, ViewBag.DropDownList as SelectList, null) 

助手类：

 public static class EnumHelper { // Get the value of the description attribute if the // enum has one, otherwise use the value. public static string GetDescription(this TEnum value) { var fi = value.GetType().GetField(value.ToString()); if (fi != null) { var attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false); if (attributes.Length > 0) { return attributes[0].Description; } } return value.ToString(); } /// 
 /// Build a select list for an enum /// 
 public static SelectList SelectListFor() where T : struct { Type t = typeof(T); return !t.IsEnum ? null : new SelectList(BuildSelectListItems(t), "Value", "Text"); } /// 
 /// Build a select list for an enum with a particular value selected /// 
 public static SelectList SelectListFor(T selected) where T : struct { Type t = typeof(T); return !t.IsEnum ? null : new SelectList(BuildSelectListItems(t), "Text", "Value", selected.ToString()); } private static IEnumerable BuildSelectListItems(Type t) { return Enum.GetValues(t) .Cast() .Select(e => new SelectListItem { Value = e.ToString(), Text = e.GetDescription() }); } } 

Answer 2

这是我在下拉列表中用于枚举的代码。 然后只需使用@ Html.DropDown / For（）; 并将此SelectList放入param中。

 public static SelectList ToSelectList(this Type enumType, string selectedValue) { var items = new List(); var selectedValueId = 0; foreach (var item in Enum.GetValues(enumType)) { FieldInfo fi = enumType.GetField(item.ToString()); DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false); var title = ""; if (attributes != null && attributes.Length > 0) { title = attributes[0].Description; } else { title = item.ToString(); } var listItem = new SelectListItem { Value = ((int)item).ToString(), Text = title, Selected = selectedValue == ((int)item).ToString(), }; items.Add(listItem); } return new SelectList(items, "Value", "Text", selectedValueId); } 

你也可以这样扩展DropDownFor：

 public static MvcHtmlString EnumDropdownListFor(this HtmlHelper htmlHelper, Expression> expression, Type enumType, object htmlAttributes = null) { ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData); SelectList selectList = enumType.ToSelectList(metadata.Model.ToString()); return htmlHelper.DropDownListFor(expression, selectList, htmlAttributes); } 

用法然后如下所示：

 @Html.EnumDropdownListFor(model => model.Property, typeof(SpecificEnum))