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C# Enum),e)}; 返回新的SelectList(值“ID”、“Name”、self); }_C#_Asp.net_Asp.net Mvc - Fatal编程技术网

C# Enum),e)}; 返回新的SelectList(值“ID”、“Name”、self); }

C# Enum),e)}; 返回新的SelectList(值“ID”、“Name”、self); },c#,asp.net,asp.net-mvc,C#,Asp.net,Asp.net Mvc,我知道我在这方面迟到了,但我想您可能会发现这个变体很有用,因为这个变体还允许您在下拉列表中使用描述性字符串而不是枚举常量。为此,请使用[System.ComponentModel.Description]属性修饰每个枚举条目 例如: public enum TestEnum { [Description("Full test")] FullTest, [Description("Incomplete or partial test")] PartialTest, [Des

我知道我在这方面迟到了,但我想您可能会发现这个变体很有用,因为这个变体还允许您在下拉列表中使用描述性字符串而不是枚举常量。为此,请使用[System.ComponentModel.Description]属性修饰每个枚举条目

例如:

public enum TestEnum
{
  [Description("Full test")]
  FullTest,

  [Description("Incomplete or partial test")]
  PartialTest,

  [Description("No test performed")]
  None
}
这是我的密码:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
using System.Web.Mvc.Html;
using System.Reflection;
using System.ComponentModel;
using System.Linq.Expressions;

 ...

 private static Type GetNonNullableModelType(ModelMetadata modelMetadata)
    {
        Type realModelType = modelMetadata.ModelType;

        Type underlyingType = Nullable.GetUnderlyingType(realModelType);
        if (underlyingType != null)
        {
            realModelType = underlyingType;
        }
        return realModelType;
    }

    private static readonly SelectListItem[] SingleEmptyItem = new[] { new SelectListItem { Text = "", Value = "" } };

    public static string GetEnumDescription<TEnum>(TEnum value)
    {
        FieldInfo fi = value.GetType().GetField(value.ToString());

        DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);

        if ((attributes != null) && (attributes.Length > 0))
            return attributes[0].Description;
        else
            return value.ToString();
    }

    public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TEnum>> expression)
    {
        return EnumDropDownListFor(htmlHelper, expression, null);
    }

    public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TEnum>> expression, object htmlAttributes)
    {
        ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
        Type enumType = GetNonNullableModelType(metadata);
        IEnumerable<TEnum> values = Enum.GetValues(enumType).Cast<TEnum>();

        IEnumerable<SelectListItem> items = from value in values
            select new SelectListItem
            {
                Text = GetEnumDescription(value),
                Value = value.ToString(),
                Selected = value.Equals(metadata.Model)
            };

        // If the enum is nullable, add an 'empty' item to the collection
        if (metadata.IsNullableValueType)
            items = SingleEmptyItem.Concat(items);

        return htmlHelper.DropDownListFor(expression, items, htmlAttributes);
    }
希望这对你有帮助

**编辑2014年1月23日:微软刚刚发布了MVC5.1,它现在有一个EnumDropDownListFor功能。遗憾的是,它似乎不尊重[Description]属性,因此上面的代码仍然有效。请参阅Microsoft的MVC 5.1发行说明

更新:它确实支持属性
[Display(Name=“Sample”)]
,因此可以使用该属性。


[更新-刚刚注意到这一点,这里的代码看起来像是代码的扩展版本:,并添加了一些内容。如果是这样,归属似乎是公平的;-)

@Simon Goldstone:感谢您的解决方案,它可以完美地应用于我的案例中。唯一的问题是我必须把它翻译成VB。但现在已经完成了,为了节省其他人的时间(以防他们需要),我把它放在这里:

Imports System.Runtime.CompilerServices
Imports System.ComponentModel
Imports System.Linq.Expressions

Public Module HtmlHelpers
    Private Function GetNonNullableModelType(modelMetadata As ModelMetadata) As Type
        Dim realModelType = modelMetadata.ModelType

        Dim underlyingType = Nullable.GetUnderlyingType(realModelType)

        If Not underlyingType Is Nothing Then
            realModelType = underlyingType
        End If

        Return realModelType
    End Function

    Private ReadOnly SingleEmptyItem() As SelectListItem = {New SelectListItem() With {.Text = "", .Value = ""}}

    Private Function GetEnumDescription(Of TEnum)(value As TEnum) As String
        Dim fi = value.GetType().GetField(value.ToString())

        Dim attributes = DirectCast(fi.GetCustomAttributes(GetType(DescriptionAttribute), False), DescriptionAttribute())

        If Not attributes Is Nothing AndAlso attributes.Length > 0 Then
            Return attributes(0).Description
        Else
            Return value.ToString()
        End If
    End Function

    <Extension()>
    Public Function EnumDropDownListFor(Of TModel, TEnum)(ByVal htmlHelper As HtmlHelper(Of TModel), expression As Expression(Of Func(Of TModel, TEnum))) As MvcHtmlString
        Return EnumDropDownListFor(htmlHelper, expression, Nothing)
    End Function

    <Extension()>
    Public Function EnumDropDownListFor(Of TModel, TEnum)(ByVal htmlHelper As HtmlHelper(Of TModel), expression As Expression(Of Func(Of TModel, TEnum)), htmlAttributes As Object) As MvcHtmlString
        Dim metaData As ModelMetadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData)
        Dim enumType As Type = GetNonNullableModelType(metaData)
        Dim values As IEnumerable(Of TEnum) = [Enum].GetValues(enumType).Cast(Of TEnum)()

        Dim items As IEnumerable(Of SelectListItem) = From value In values
            Select New SelectListItem With
            {
                .Text = GetEnumDescription(value),
                .Value = value.ToString(),
                .Selected = value.Equals(metaData.Model)
            }

        ' If the enum is nullable, add an 'empty' item to the collection
        If metaData.IsNullableValueType Then
            items = SingleEmptyItem.Concat(items)
        End If

        Return htmlHelper.DropDownListFor(expression, items, htmlAttributes)
    End Function
End Module

您还可以在Griffin.MvcContrib中使用我的自定义HtmlHelpers。以下代码:

public static SelectList ToSelectList<T, TU>(T enumObj) 
    where T : struct
    where TU : struct
{
    if(!typeof(T).IsEnum) throw new ArgumentException("Enum is required.", "enumObj");

    var values = from T e in Enum.GetValues(typeof(T))
                 select new { 
                    Value = (TU)Convert.ChangeType(e, typeof(TU)),
                    Text = e.ToString() 
                 };

    return new SelectList(values, "Value", "Text", enumObj);
}
@Html2.CheckBoxesFor(model => model.InputType) <br />
@Html2.RadioButtonsFor(model => model.InputType) <br />
@Html2.DropdownFor(model => model.InputType) <br />
@Html2.CheckBoxesFor(model=>model.InputType)
@Html2.RadioButtonsFor(model=>model.InputType)
@Html2.DropdownFor(model=>model.InputType)
生成:


这是符文&Prise答案,更改为使用Enum
int
值作为ID

样本枚举:

public enum ItemTypes
{
    Movie = 1,
    Game = 2,
    Book = 3
}
扩展方法:

namespace MyApp.Common
{
    public static class MyExtensions{
        public static SelectList ToSelectList<TEnum>(this TEnum enumObj)
            where TEnum : struct, IComparable, IFormattable, IConvertible
        {
            var values = from TEnum e in Enum.GetValues(typeof(TEnum))
                select new { Id = e, Name = e.ToString() };
            return new SelectList(values, "Id", "Name", enumObj);
        }
    }
}
    public static SelectList ToSelectList<TEnum>(this TEnum enumObj)
    {
        var values = from TEnum e in Enum.GetValues(typeof(TEnum))
                     select new { Id = (int)Enum.Parse(typeof(TEnum), e.ToString()), Name = e.ToString() };

        return new SelectList(values, "Id", "Name", (int)Enum.Parse(typeof(TEnum), enumObj.ToString()));
    }
public static SelectList to SelectList(此十进制枚举对象)
{
var values=从Enum.GetValues中的TEnum e开始(typeof(TEnum))
选择新的{Id=(int)Enum.Parse(typeof(TEnum),e.ToString()),Name=e.ToString();
返回新的SelectList(值,“Id”,“Name”,“int”)Enum.Parse(typeof(TEnum),enumObj.ToString());
}
用法示例:

 <%=  Html.DropDownList("MyEnumList", ItemTypes.Game.ToSelectList()) %>

请记住导入包含扩展方法的命名空间

<%@ Import Namespace="MyNamespace.LocationOfExtensionMethod" %>

生成的HTML示例:

<select id="MyEnumList" name="MyEnumList">
    <option value="1">Movie</option>
    <option selected="selected" value="2">Game</option>
    <option value="3">Book </option>
</select>

电影
游戏
书

请注意,您用来调用上的
ToSelectList
的项目就是所选项目。

我找到的最佳解决方案是与

这允许在模型中使用枚举。其基本思想是使用integer属性和enum,并模拟integer属性

然后使用[System.ComponentModel.Description]属性用显示文本注释模型,并在视图中使用“EnumDropDownListFor”扩展名

这使得视图和模型都非常可读和可维护

型号:

public enum YesPartialNoEnum
{
    [Description("Yes")]
    Yes,
    [Description("Still undecided")]
    Partial,
    [Description("No")]
    No
}

//........

[Display(Name = "The label for my dropdown list")]
public virtual Nullable<YesPartialNoEnum> CuriousQuestion{ get; set; }
public virtual Nullable<int> CuriousQuestionId
{
    get { return (Nullable<int>)CuriousQuestion; }
    set { CuriousQuestion = (Nullable<YesPartialNoEnum>)value; }
}
扩展(直接来自,为完整起见包括在此处):

使用系统;
使用System.Collections.Generic;
使用System.Linq;
使用System.Web;
使用System.Web.Mvc;
使用系统组件模型;
运用系统反思;
使用System.Linq.Expressions;
使用System.Web.Mvc.Html;
命名空间MyProject.Extensions
{
//扩展方法必须在静态类中定义
公共静态类MvcExtensions
{
私有静态类型GetNonNullableModelType(ModelMetadata ModelMetadata)
{
类型realModelType=modelMetadata.ModelType;
类型underlyingType=Nullable.GetUnderlyingType(realModelType);
if(underlyngtype!=null)
{
realModelType=underyingtype;
}
返回realModelType;
}
私有静态只读SelectListItem[]SingleEmptyItem=new[]{new SelectListItem{Text=”“,Value=”“};
公共静态字符串GetEnumDescription(TEnum值)
{
FieldInfo fi=value.GetType().GetField(value.ToString());
DescriptionAttribute[]attributes=(DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute),false);
如果((attributes!=null)&&(attributes.Length>0))
返回属性[0]。说明;
其他的
返回值.ToString();
}
公共静态MvcHtmlString EnumDropDownListFor(此HtmlHelper HtmlHelper,表达式)
{
返回EnumDropDownListFor(htmlHelper,表达式,null);
}
公共静态MvcHtmlString EnumDropDownListFor(此HtmlHelper HtmlHelper、表达式、对象htmlAttributes)
{
ModelMetadata元数据=ModelMetadata.FromLambdaExpression(表达式,htmlHelper.ViewData);
类型enumType=GetNonNullableModelType(元数据);
IEnumerable values=Enum.GetValues(enumType.Cast();
IEnumerable items=来自值中的值
选择新的SelectListItem
{
Text=GetEnumDescription(值),
Value=Value.ToString(),
所选=value.Equals(metadata.Model)
};
//如果枚举可为空,请向集合中添加“空”项
if(metadata.IsNullableValueType)
items=SingleEmptyItem.Concat(项目);
返回htmlHelper.DropDownListFor(表达式、项、htmlAttributes);
}
}
}

这是Razor的版本:

@{
    var itemTypesList = new List<SelectListItem>();
    itemTypesList.AddRange(Enum.GetValues(typeof(ItemTypes)).Cast<ItemTypes>().Select(
                (item, index) => new SelectListItem
                {
                    Text = item.ToString(),
                    Value = (index).ToString(),
                    Selected = Model.ItemTypeId == index
                }).ToList());
 }


@Html.DropDownList("ItemTypeId", itemTypesList)
@{
var itemTypesList=新列表();
itemTypesList.AddRange(Enum.GetValues(typeof(ItemTypes)).Cast()。选择(
(项目,索引)=>新建SelectListItem
{
Text=item.ToString(),
值=(索引).ToString(),
所选=Model.ItemTypeId==索引
}).ToList());
}
@Html.DropDownList(“ItemTypeId”,
ResourceManager rManager = new ResourceManager(typeof(Resources));
var dayTypes = from OperatorCalendarDay.OperatorDayType s in Enum.GetValues(typeof(OperatorCalendarDay.OperatorDayType))
               select new { ID = s, Name = rManager.GetString(s.ToString()) };
var values = from int e in Enum.GetValues(typeof(TEnum))
             select new { ID = e, Name = Enum.GetName(typeof(TEnum), e) };
var values = from TEnum e in Enum.GetValues(typeof(TEnum))
           select new { ID = (int)Enum.Parse(typeof(TEnum),e.ToString())
                     , Name = e.ToString() };
public static SelectList ToSelectList<TEnum>(this TEnum self) where TEnum : struct
    {
        if (!typeof(TEnum).IsEnum)
        {
            throw new ArgumentException("self must be enum", "self");
        }

        Type t = typeof(TEnum);

        var values = from int e in Enum.GetValues(typeof(TEnum))
                     select new { ID = e, Name = Enum.GetName(typeof(TEnum), e) };

        return new SelectList(values, "ID", "Name", self);
    }
public enum TestEnum
{
  [Description("Full test")]
  FullTest,

  [Description("Incomplete or partial test")]
  PartialTest,

  [Description("No test performed")]
  None
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
using System.Web.Mvc.Html;
using System.Reflection;
using System.ComponentModel;
using System.Linq.Expressions;

 ...

 private static Type GetNonNullableModelType(ModelMetadata modelMetadata)
    {
        Type realModelType = modelMetadata.ModelType;

        Type underlyingType = Nullable.GetUnderlyingType(realModelType);
        if (underlyingType != null)
        {
            realModelType = underlyingType;
        }
        return realModelType;
    }

    private static readonly SelectListItem[] SingleEmptyItem = new[] { new SelectListItem { Text = "", Value = "" } };

    public static string GetEnumDescription<TEnum>(TEnum value)
    {
        FieldInfo fi = value.GetType().GetField(value.ToString());

        DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);

        if ((attributes != null) && (attributes.Length > 0))
            return attributes[0].Description;
        else
            return value.ToString();
    }

    public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TEnum>> expression)
    {
        return EnumDropDownListFor(htmlHelper, expression, null);
    }

    public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TEnum>> expression, object htmlAttributes)
    {
        ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
        Type enumType = GetNonNullableModelType(metadata);
        IEnumerable<TEnum> values = Enum.GetValues(enumType).Cast<TEnum>();

        IEnumerable<SelectListItem> items = from value in values
            select new SelectListItem
            {
                Text = GetEnumDescription(value),
                Value = value.ToString(),
                Selected = value.Equals(metadata.Model)
            };

        // If the enum is nullable, add an 'empty' item to the collection
        if (metadata.IsNullableValueType)
            items = SingleEmptyItem.Concat(items);

        return htmlHelper.DropDownListFor(expression, items, htmlAttributes);
    }
@Html.EnumDropDownListFor(model => model.MyEnumProperty)
Imports System.Runtime.CompilerServices
Imports System.ComponentModel
Imports System.Linq.Expressions

Public Module HtmlHelpers
    Private Function GetNonNullableModelType(modelMetadata As ModelMetadata) As Type
        Dim realModelType = modelMetadata.ModelType

        Dim underlyingType = Nullable.GetUnderlyingType(realModelType)

        If Not underlyingType Is Nothing Then
            realModelType = underlyingType
        End If

        Return realModelType
    End Function

    Private ReadOnly SingleEmptyItem() As SelectListItem = {New SelectListItem() With {.Text = "", .Value = ""}}

    Private Function GetEnumDescription(Of TEnum)(value As TEnum) As String
        Dim fi = value.GetType().GetField(value.ToString())

        Dim attributes = DirectCast(fi.GetCustomAttributes(GetType(DescriptionAttribute), False), DescriptionAttribute())

        If Not attributes Is Nothing AndAlso attributes.Length > 0 Then
            Return attributes(0).Description
        Else
            Return value.ToString()
        End If
    End Function

    <Extension()>
    Public Function EnumDropDownListFor(Of TModel, TEnum)(ByVal htmlHelper As HtmlHelper(Of TModel), expression As Expression(Of Func(Of TModel, TEnum))) As MvcHtmlString
        Return EnumDropDownListFor(htmlHelper, expression, Nothing)
    End Function

    <Extension()>
    Public Function EnumDropDownListFor(Of TModel, TEnum)(ByVal htmlHelper As HtmlHelper(Of TModel), expression As Expression(Of Func(Of TModel, TEnum)), htmlAttributes As Object) As MvcHtmlString
        Dim metaData As ModelMetadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData)
        Dim enumType As Type = GetNonNullableModelType(metaData)
        Dim values As IEnumerable(Of TEnum) = [Enum].GetValues(enumType).Cast(Of TEnum)()

        Dim items As IEnumerable(Of SelectListItem) = From value In values
            Select New SelectListItem With
            {
                .Text = GetEnumDescription(value),
                .Value = value.ToString(),
                .Selected = value.Equals(metaData.Model)
            }

        ' If the enum is nullable, add an 'empty' item to the collection
        If metaData.IsNullableValueType Then
            items = SingleEmptyItem.Concat(items)
        End If

        Return htmlHelper.DropDownListFor(expression, items, htmlAttributes)
    End Function
End Module
@Html.EnumDropDownListFor(Function(model) (model.EnumField))
@Html2.CheckBoxesFor(model => model.InputType) <br />
@Html2.RadioButtonsFor(model => model.InputType) <br />
@Html2.DropdownFor(model => model.InputType) <br />
public enum ItemTypes
{
    Movie = 1,
    Game = 2,
    Book = 3
}
    public static SelectList ToSelectList<TEnum>(this TEnum enumObj)
    {
        var values = from TEnum e in Enum.GetValues(typeof(TEnum))
                     select new { Id = (int)Enum.Parse(typeof(TEnum), e.ToString()), Name = e.ToString() };

        return new SelectList(values, "Id", "Name", (int)Enum.Parse(typeof(TEnum), enumObj.ToString()));
    }
 <%=  Html.DropDownList("MyEnumList", ItemTypes.Game.ToSelectList()) %>
<%@ Import Namespace="MyNamespace.LocationOfExtensionMethod" %>
<select id="MyEnumList" name="MyEnumList">
    <option value="1">Movie</option>
    <option selected="selected" value="2">Game</option>
    <option value="3">Book </option>
</select>
public enum YesPartialNoEnum
{
    [Description("Yes")]
    Yes,
    [Description("Still undecided")]
    Partial,
    [Description("No")]
    No
}

//........

[Display(Name = "The label for my dropdown list")]
public virtual Nullable<YesPartialNoEnum> CuriousQuestion{ get; set; }
public virtual Nullable<int> CuriousQuestionId
{
    get { return (Nullable<int>)CuriousQuestion; }
    set { CuriousQuestion = (Nullable<YesPartialNoEnum>)value; }
}
@using MyProject.Extensions
{
//...
    @Html.EnumDropDownListFor(model => model.CuriousQuestion)
//...
}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.ComponentModel;
using System.Reflection;
using System.Linq.Expressions;
using System.Web.Mvc.Html;

namespace MyProject.Extensions
{
    //Extension methods must be defined in a static class
    public static class MvcExtensions
    {
        private static Type GetNonNullableModelType(ModelMetadata modelMetadata)
        {
            Type realModelType = modelMetadata.ModelType;

            Type underlyingType = Nullable.GetUnderlyingType(realModelType);
            if (underlyingType != null)
            {
                realModelType = underlyingType;
            }
            return realModelType;
        }

        private static readonly SelectListItem[] SingleEmptyItem = new[] { new SelectListItem { Text = "", Value = "" } };

        public static string GetEnumDescription<TEnum>(TEnum value)
        {
            FieldInfo fi = value.GetType().GetField(value.ToString());

            DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);

            if ((attributes != null) && (attributes.Length > 0))
                return attributes[0].Description;
            else
                return value.ToString();
        }

        public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TEnum>> expression)
        {
            return EnumDropDownListFor(htmlHelper, expression, null);
        }

        public static MvcHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> htmlHelper, Expression<Func<TModel, TEnum>> expression, object htmlAttributes)
        {
            ModelMetadata metadata = ModelMetadata.FromLambdaExpression(expression, htmlHelper.ViewData);
            Type enumType = GetNonNullableModelType(metadata);
            IEnumerable<TEnum> values = Enum.GetValues(enumType).Cast<TEnum>();

            IEnumerable<SelectListItem> items = from value in values
                                                select new SelectListItem
                                                {
                                                    Text = GetEnumDescription(value),
                                                    Value = value.ToString(),
                                                    Selected = value.Equals(metadata.Model)
                                                };

            // If the enum is nullable, add an 'empty' item to the collection
            if (metadata.IsNullableValueType)
                items = SingleEmptyItem.Concat(items);

            return htmlHelper.DropDownListFor(expression, items, htmlAttributes);
        }
    }
}
@{
    var itemTypesList = new List<SelectListItem>();
    itemTypesList.AddRange(Enum.GetValues(typeof(ItemTypes)).Cast<ItemTypes>().Select(
                (item, index) => new SelectListItem
                {
                    Text = item.ToString(),
                    Value = (index).ToString(),
                    Selected = Model.ItemTypeId == index
                }).ToList());
 }


@Html.DropDownList("ItemTypeId", itemTypesList)
//Replace "YourEnum" with the type of your enum
public IEnumerable<SelectListItem> AllItems
{
    get
    {
        return Enums.GetValues<YourEnum>().Select(enumValue => new SelectListItem { Value = enumValue.ToString(), Text = enumValue.GetDescription() });
    }
}
public static class EnumEditorHtmlHelper
{
    /// <summary>
    /// Creates the DropDown List (HTML Select Element) from LINQ 
    /// Expression where the expression returns an Enum type.
    /// </summary>
    /// <typeparam name="TModel">The type of the model.</typeparam>
    /// <typeparam name="TProperty">The type of the property.</typeparam>
    /// <param name="htmlHelper">The HTML helper.</param>
    /// <param name="expression">The expression.</param>
    /// <returns></returns>
    public static MvcHtmlString DropDownListFor<TModel, TProperty>(this HtmlHelper<TModel> htmlHelper,
        Expression<Func<TModel, TProperty>> expression) 
        where TModel : class
    {
        TProperty value = htmlHelper.ViewData.Model == null 
            ? default(TProperty) 
            : expression.Compile()(htmlHelper.ViewData.Model);
        string selected = value == null ? String.Empty : value.ToString();
        return htmlHelper.DropDownListFor(expression, createSelectList(expression.ReturnType, selected));
    }

    /// <summary>
    /// Creates the select list.
    /// </summary>
    /// <param name="enumType">Type of the enum.</param>
    /// <param name="selectedItem">The selected item.</param>
    /// <returns></returns>
    private static IEnumerable<SelectListItem> createSelectList(Type enumType, string selectedItem)
    {
        return (from object item in Enum.GetValues(enumType)
                let fi = enumType.GetField(item.ToString())
                let attribute = fi.GetCustomAttributes(typeof (DescriptionAttribute), true).FirstOrDefault()
                let title = attribute == null ? item.ToString() : ((DescriptionAttribute) attribute).Description
                select new SelectListItem
                  {
                      Value = item.ToString(), 
                      Text = title, 
                      Selected = selectedItem == item.ToString()
                  }).ToList();
    }
}
public static IHtmlString EnumDropDownListFor<TModel, TEnum>(this HtmlHelper<TModel> html, Expression<Func<TModel, TEnum>> expression)
{            
    var metadata = ModelMetadata.FromLambdaExpression(expression, html.ViewData);

    var enumType = Nullable.GetUnderlyingType(metadata.ModelType) ?? metadata.ModelType;

    var enumValues = Enum.GetValues(enumType).Cast<object>();

    var items = from enumValue in enumValues                        
                select new SelectListItem
                {
                    Text = GetResourceValueForEnumValue(enumValue),
                    Value = ((int)enumValue).ToString(),
                    Selected = enumValue.Equals(metadata.Model)
                };


    return html.DropDownListFor(expression, items, string.Empty, null);
}

private static string GetResourceValueForEnumValue<TEnum>(TEnum enumValue)
{
    var key = string.Format("{0}_{1}", enumValue.GetType().Name, enumValue);

    return Enums.ResourceManager.GetString(key) ?? enumValue.ToString();
}
@using MVCProject.Extensions

@{
    var type = Nullable.GetUnderlyingType(ViewData.ModelMetadata.ModelType) ?? ViewData.ModelMetadata.ModelType;

    @(typeof (Enum).IsAssignableFrom(type) ? Html.EnumDropDownListFor(x => x) : Html.TextBoxFor(x => x))
}
@Html.DropdownListFor(model=model->Gender,new List<SelectListItem>
{
 new ListItem{Text="Male",Value="Male"},
 new ListItem{Text="Female",Value="Female"},
 new ListItem{Text="--- Select -----",Value="-----Select ----"}
}
)
@Html.DropDownListFor(model => model.MaritalStatus, new List<SelectListItem> 
{  

new SelectListItem { Text = "----Select----", Value = "-1" },


new SelectListItem { Text = "Marrid", Value = "M" },


 new SelectListItem { Text = "Single", Value = "S" }

})
//If you don't have an enum value use the type
ViewBag.DropDownList = EnumHelper.SelectListFor<MyEnum>();

//If you do have an enum value use the value (the value will be marked as selected)    
ViewBag.DropDownList = EnumHelper.SelectListFor(MyEnum.MyEnumValue);
@Html.DropDownList("DropDownList")
@* OR *@
@Html.DropDownListFor(m => m.Property, ViewBag.DropDownList as SelectList, null)
public static class EnumHelper
{
    // Get the value of the description attribute if the   
    // enum has one, otherwise use the value.  
    public static string GetDescription<TEnum>(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();
    }

    /// <summary>
    /// Build a select list for an enum
    /// </summary>
    public static SelectList SelectListFor<T>() where T : struct
    {
        Type t = typeof(T);
        return !t.IsEnum ? null
                         : new SelectList(BuildSelectListItems(t), "Value", "Text");
    }

    /// <summary>
    /// Build a select list for an enum with a particular value selected 
    /// </summary>
    public static SelectList SelectListFor<T>(T selected) where T : struct
    {
        Type t = typeof(T);
        return !t.IsEnum ? null
                         : new SelectList(BuildSelectListItems(t), "Text", "Value", selected.ToString());
    }

    private static IEnumerable<SelectListItem> BuildSelectListItems(Type t)
    {
        return Enum.GetValues(t)
                   .Cast<Enum>()
                   .Select(e => new SelectListItem { Value = e.ToString(), Text = e.GetDescription() });
    }
}
@Html.DropDownListFor(model => model.Type, Enum.GetNames(typeof(Rewards.Models.PropertyType)).Select(e => new SelectListItem { Text = e }))
public enum MyEnum
{
    [Display(Name = "First Value - desc..")]
    FirstValue,
    [Display(Name = "Second Value - desc...")]
    SecondValue
}
@Html.EnumDropDownListFor(model => model.MyEnum)
<select asp-for="@Model.SelectedValue" asp-items="Html.GetEnumSelectList<MyEnum>()">
    public enum SelectedLevel
    {
       Level1,
       Level2,
       Level3,
       Level4
    }
    List<SelectedLevel> myLevels = Enum.GetValues(typeof(SelectedLevel)).Cast<SelectedLevel>().ToList();
    ViewBag.RequiredLevel = new SelectList(myLevels);
    @Html.DropDownList("selectedLevel", (SelectList)ViewBag.RequiredLevel, new { @class = "form-control" })
public enum AccessLevelEnum
    {
        /// <summary>
        /// The user cannot access
        /// </summary>
        [EnumMember, Description("No Access")]
        NoAccess = 0x0,

        /// <summary>
        /// The user can read the entire record in question
        /// </summary>
        [EnumMember, Description("Read Only")]
        ReadOnly = 0x01,

        /// <summary>
        /// The user can read or write
        /// </summary>
        [EnumMember, Description("Read / Modify")]
        ReadModify = 0x02,

        /// <summary>
        /// User can create new records, modify and read existing ones
        /// </summary>
        [EnumMember, Description("Create / Read / Modify")]
        CreateReadModify = 0x04,

        /// <summary>
        /// User can read, write, or delete
        /// </summary>
        [EnumMember, Description("Create / Read / Modify / Delete")]
        CreateReadModifyDelete = 0x08,

        /*/// <summary>
        /// User can read, write, or delete
        /// </summary>
        [EnumMember, Description("Create / Read / Modify / Delete / Verify / Edit Capture Value")]
        CreateReadModifyDeleteVerify = 0x16*/
    }
@Html.DropDownList("accessLevel",new SelectList(AccessLevelEnum.GetValues(typeof(AccessLevelEnum))),new { @class = "form-control" })
@Html.DropDownListFor(m=>m.accessLevel,new SelectList(AccessLevelEnum.GetValues(typeof(AccessLevelEnum))),new { @class = "form-control" })
@Html.DropDownListFor(m=>m.accessLevel,new SelectList(AccessLevelEnum.GetValues(typeof(AccessLevelEnum)) , AccessLevelEnum.NoAccess ),new { @class = "form-control" })
@Html.DropDownListFor(x => x.Foo, Html.GetEnumSelectList<MyEnum>())