MVC中下拉框显示枚举项

时间:2024-01-05 08:55:26

原文:MVC中下拉框显示枚举项

本篇将通过3种方式,把枚举项上的自定义属性填充到下拉框:
1、通过控制器返回List<SelectListItem>类型给前台视图
2、通过为枚举类型属性打上UIHint属性让模版显示枚举项
3、通过自定义元数据提供器DataAnnotationsModelMetadataProvider让模版显示枚举项

 

我们经常会把类型为Int16的属性通过枚举来获得。比如:

public class SomeClass
{
public int16 Status{get;set;}
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

对应的枚举:

public enum StatusEnum
{
    Enable = 0,
    Disable = 1
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

在MVC视图中可能会这样写:

<select id="sel">
   <option value="">==选择状态==</option>
   <option value="0">启用</option>
   <option value="1">禁用</option>
</select>

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

如果枚举的项发生变化怎么办?比如:

public enum StatusEnum
{
    Enable = 0,
    Disable = 1,
    NeverComeback = 2
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

如果修改每一页的代码,显然是不合理的。最理想的做法是:为每一个枚举项打上属性,显示的时候直接读取枚举以及枚举项属性值。

 

  通过控制器返回List<SelectListItem>类型给前台视图

定义一个Model,其中有一个类型为Int16的属性Status,这个属性用来接收枚举值。

using System;
using System.ComponentModel.DataAnnotations;
 
namespace MvcApplication1.Models
{
    public class Stadium
    {
        public int Id { get; set; }
 
        [Display(Name = "场馆名称")]
        public string Name { get; set; }
 
        [Display(Name = "是否启用")]
        public Int16 Status { get; set; }
    }
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

为每个枚举项打上的属性需要我们自定义,通过构造函数接收名称,并提供一个属性供外部访问。

using System;
 
namespace MvcApplication1.Extension
{
    public class EnumDisplayNameAttribute : Attribute
    {
        private string _displayName;
 
        public EnumDisplayNameAttribute(string displayName)
        {
            this._displayName = displayName;
        }
 
        public string DisplayName
        {
            get { return _displayName; }
        }
    }
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

为每个枚举项打上自定义属性。

using MvcApplication1.Extension;
 
namespace MvcApplication1.Models.Enum
{
    public enum StatusEnum
    {
        [EnumDisplayName("启用")]
        Enable = 0,
        [EnumDisplayName("禁用")]
        Disable =  1
    }
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

我们的目的是在控制器获取List<SelectListItem>集合,然后传递到前台视图。现在,枚举和枚举项上的自定义属性都有了,有必要创建一个帮助类来帮我们获取List<SelectListItem>集合。

using System;
using System.Collections.Generic;
using System.Reflection;
using System.Web.Mvc;
 
namespace MvcApplication1.Extension
{
    public class EnumExt
    {
        /// <summary>
        /// 根据枚举成员获取自定义属性EnumDisplayNameAttribute的属性DisplayName
        /// </summary>
        /// <param name="e"></param>
        /// <returns></returns>
        public static string GetEnumCustomDescription(object e)
        {
            //获取枚举的Type类型对象
            Type t = e.GetType();
 
            //获取枚举的所有字段
            FieldInfo[] ms = t.GetFields();
 
            //遍历所有枚举的所有字段
            foreach (FieldInfo f in ms)
            {
                if (f.Name != e.ToString())
                {
                    continue;
                }
 
                //第二个参数true表示查找EnumDisplayNameAttribute的继承链
                if (f.IsDefined(typeof (EnumDisplayNameAttribute), true))
                {
                    return
                        (f.GetCustomAttributes(typeof(EnumDisplayNameAttribute), true)[0] as EnumDisplayNameAttribute)
                            .DisplayName;
                }
            }
 
            //如果没有找到自定义属性,直接返回属性项的名称
            return e.ToString();
        }
 
        /// <summary>
        /// 根据枚举,把枚举自定义特性EnumDisplayNameAttribut的Display属性值撞到SelectListItem中
        /// </summary>
        /// <param name="enumType">枚举</param>
        /// <returns></returns>
        public static List<SelectListItem> GetSelectList(Type enumType)
        {
            List<SelectListItem> selectList = new List<SelectListItem>();
            foreach (object e in Enum.GetValues(enumType))
            {
                selectList.Add(new SelectListItem(){Text = GetEnumCustomDescription(e),Value = ((int)e).ToString()});
            }
            return selectList;
        }
    }
}
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

在控制器中,通过ViewData把List<SelectListItem>集合往前台传。控制器包含2个方法,一个方法用来显示创建视图界面,另一个用来显示编辑视图界面。

        //创建
        public ActionResult Index()
        {
            ViewData["s"] = EnumExt.GetSelectList(typeof (StatusEnum));
            return View(new Stadium());
        }
 
        //编辑
        public ActionResult Edit()
        {
            Stadium s = new Stadium()
            {
                Id = 2,
                Name = "水立方",
                Status = (short)StatusEnum.Disable
            };
            ViewData["s"] = EnumExt.GetSelectList(typeof(StatusEnum));
            return View(s);
        }

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

在强类型的创建视图界面中,通过@Html.DropDownListFor(model => model.Status,(List<SelectListItem>)ViewData["s"])接收来自控制器的数据。

@model MvcApplication1.Models.Stadium
 
@{
    ViewBag.Title = "Index";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
 
<h2>Index</h2>
 
@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
 
    <fieldset>
        <legend>Stadium</legend>
 
        <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.Status)
        </div>
        <div class="editor-field">
            @Html.DropDownListFor(model => model.Status,(List<SelectListItem>)ViewData["s"])
            @Html.ValidationMessageFor(model => model.Status)
        </div>
 
        <p>
            <input type="submit" value="添加" />
        </p>
    </fieldset>
}
 
 
@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

在强类型的编辑视图界面中,同样通过@Html.DropDownListFor(model => model.Status,(List<SelectListItem>)ViewData["s"])接收来自控制器的数据。

@model MvcApplication1.Models.Stadium
 
@{
    ViewBag.Title = "Edit";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
 
<h2>Edit</h2>
 
@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
 
    <fieldset>
        <legend>Stadium</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.Status)
        </div>
        <div class="editor-field">
             @Html.DropDownListFor(model => model.Status,(List<SelectListItem>)ViewData["s"])
            @Html.ValidationMessageFor(model => model.Status)
        </div>
 
        <p>
            <input type="submit" value="编辑" />
        </p>
    </fieldset>
}
 
 
@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

创建界面:

MVC中下拉框显示枚举项

 

编辑界面:

MVC中下拉框显示枚举项

 

  通过为枚举类型属性打上UIHint属性让模版显示枚举项

由于模版是根据属性类型来判断的,再定义一个Model,其中一个属性类型是枚举。

using System.ComponentModel.DataAnnotations;
using MvcApplication1.Models.Enum;
 
namespace MvcApplication1.Models
{
    public class Stadium1
    {
        public int Id { get; set; }
 
        [Display(Name = "场馆名称")]
        public string Name { get; set; }
 
        [Display(Name = "是否启用")]
        public StatusEnum Status { get; set; } 
    }
}

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

在Views/Shared/EditorTemplates文件夹下创建Enum.cshtml,用来处理类型为Enum的属性。

@using System.ComponentModel.DataAnnotations
@using System.Reflection
@using MvcApplication1.Extension
 
@{
    var selectList = new List<SelectListItem>();
    string optionLabel = null;
    object htmlAttributes = null;
    var enumType = (Type)Model.GetType();
    foreach (var value in Enum.GetValues(enumType))
    {
        var field = enumType.GetField(value.ToString());
        var option = new SelectListItem() {Value = value.ToString()};
        var display = field.GetCustomAttributes(typeof (EnumDisplayNameAttribute), false).FirstOrDefault() as EnumDisplayNameAttribute;
        if (display != null)
        {
            option.Text = display.DisplayName;
        }
        else
        {
            option.Text = value.ToString();
        }
        option.Selected = object.Equals(value, Model);
        selectList.Add(option);
    }
}
 
@Html.DropDownList("",selectList, optionLabel, htmlAttributes)
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

控制器中有2个方法用来显示创建和编辑视图界面。

        //创建
        public ActionResult TemplateCreate()
        {
            return View(new Stadium1());
        }
 
        //编辑
        public ActionResult TemplateEdit()
        {
            Stadium1 s = new Stadium1()
            {
                Id = 2,
                Name = "水立方",
                Status = StatusEnum.Disable
            };
            return View(s);
        }

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

强类型的创建视图界面:

@model MvcApplication1.Models.Stadium1
 
@{
    ViewBag.Title = "TemplateCreate";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
 
<h2>TemplateCreate</h2>
 
@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
 
    <fieldset>
        <legend>Stadium</legend>
 
        <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.Status)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Status)
            @Html.ValidationMessageFor(model => model.Status)
        </div>
 
        <p>
            <input type="submit" value="Create" />
        </p>
    </fieldset>
}
 
 
@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

强类型的编辑视图界面:

@model MvcApplication1.Models.Stadium1
 
@{
    ViewBag.Title = "TemplateEdit";
    Layout = "~/Views/Shared/_Layout.cshtml";
}
 
<h2>TemplateEdit</h2>
 
@using (Html.BeginForm()) {
    @Html.ValidationSummary(true)
 
    <fieldset>
        <legend>Stadium</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.Status)
        </div>
        <div class="editor-field">
            @Html.EditorFor(model => model.Status)
            @Html.ValidationMessageFor(model => model.Status)
        </div>
 
        <p>
            <input type="submit" value="Save" />
        </p>
    </fieldset>
}
 
 
@section Scripts {
    @Scripts.Render("~/bundles/jqueryval")
}
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

最后,给Stadium1的枚举属性,打上UIHint属性,指明使用公共Enum类型模版Views/Shared/EditorTemplates/Enum.cshtml。

using System.ComponentModel.DataAnnotations;
using MvcApplication1.Models.Enum;
 
namespace MvcApplication1.Models
{
    public class Stadium1
    {
        public int Id { get; set; }
 
        [Display(Name = "场馆名称")]
        public string Name { get; set; }
 
        [Display(Name = "是否启用")]
        [UIHint("Enum")]
        public StatusEnum Status { get; set; } 
    }
}
 

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

 

创建视图界面:

MVC中下拉框显示枚举项

编辑视图界面:

MVC中下拉框显示枚举项

 

  通过自定义元数据提供器DataAnnotationsModelMetadataProvider让模版显示枚举项

如果觉得为属性打上[UIHint("Enum")]属性麻烦的话,还可以通过数据提供器,为所有类型为Enum的属性指明模版。

MVC中下拉框显示枚举项

 

当然自定义的元数据提供器是需要在全局中注册的。

    public class MvcApplication : System.Web.HttpApplication
    {
        protected void Application_Start()
        {
            AreaRegistration.RegisterAllAreas();
 
            WebApiConfig.Register(GlobalConfiguration.Configuration);
            FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters);
            RouteConfig.RegisterRoutes(RouteTable.Routes);
            BundleConfig.RegisterBundles(BundleTable.Bundles);
 
            //注册自定义元数据提供其
            ModelMetadataProviders.Current = new CustomMetadataProvider();
        }
    }

.csharpcode, .csharpcode pre
{
font-size: small;
color: black;
font-family: consolas, "Courier New", courier, monospace;
background-color: #ffffff;
/*white-space: pre;*/
}
.csharpcode pre { margin: 0em; }
.csharpcode .rem { color: #008000; }
.csharpcode .kwrd { color: #0000ff; }
.csharpcode .str { color: #006080; }
.csharpcode .op { color: #0000c0; }
.csharpcode .preproc { color: #cc6633; }
.csharpcode .asp { background-color: #ffff00; }
.csharpcode .html { color: #800000; }
.csharpcode .attr { color: #ff0000; }
.csharpcode .alt
{
background-color: #f4f4f4;
width: 100%;
margin: 0em;
}
.csharpcode .lnum { color: #606060; }

现在可以把Stadium的[UIHint("Enum")]注释掉。

 

  总结

如果,我们想在下拉框中显示枚举项,首先给枚举项打上自定义属性,通过反射可以拿到自定义属性的相关属性值。

如果,想在控制器方法中获取List<SelectListItem>集合往前台传,我们可以封装一个方法,根据枚举返回List<SelectListItem>集合;

如果想根据属性的类型显示枚举模版,要么给枚举属性打上[UIHint("Enum")],要么在全局自定义一个DataAnnotationsModelMetadataProvider。