Enum枚举的使用

例：
要求select下拉列表展示枚举中所有项

枚举类：

public enum AdverType
{
    [Description("跨栏广告")]
    HurdleAdverType = 0,
    [Description("分栏广告")]
    ColumnAdverType = 1,
}

控制器类:

    public IActionResult AdvertModify(string Id)
    {
        ViewBag.modelAdverType = EnumHelper.GetEnumModel<AdverType>();
        ViewBag.Id = Id;
        return View();
    }

页面调用：

image.png

获得枚举的描述：

1.控制器

    public IActionResult Index()
    {
        ViewBag.modelAdverType = EnumHelper.GetEnumModel<AdverType>();
        ViewBag.modelAdverTypeJson = Newtonsoft.Json.JsonConvert.SerializeObject(ViewBag.modelAdverType);
        return View();
    }

js调用

var advertType = JSON.parse('@Html.Raw(ViewBag.modelAdverTypeJson)');
AdvertType.find(p => p.Value == advertType ).Description;

2.后台方法调用

 public string GetEnumDes(string value)
    {
        var listenum = EnumHelper.GetEnumModel<AdverType>();
        var des=listenum.Find(p => p.Value == value).Description;
        return des;
    }

枚举帮助类：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Reflection;
using System.Text;

namespace EnumHelpLL.Infrastructure.Utility
{
   public class EnumHelper
{
    /// <summary>
    /// 用于保存枚举值Name,Value,Description的类
    /// </summary>
    public class EnumModel
    {
        public string Description { get; set; }
        public string Name { get; set; }
        public int Value { get; set; }
    }

    /// <summary>
    /// 获取枚举的Name,Value,Description
    /// </summary>
    /// <typeparam name="T">枚举</typeparam>
    /// <returns></returns>
    public static List<EnumModel> GetEnumModel<T>()
    {
        List<EnumModel> listEnumModel = new List<EnumModel>();

        #region
        /*
         * 表示类型声明，类类型，接口类型，数组类型，值类型，枚举类型，类型参数，泛型类型定义，以及开放或封闭构造的泛型。
         */
        #endregion
        Type type = typeof(T);
        #region 
        /*
         * FieldInfo http://msdn.microsoft.com/zh-cn/library/system.reflection.fieldinfo(v=vs.95).aspx
         * 
         */
        #endregion
        FieldInfo[] fieldInfos = type.GetFields();
        foreach (FieldInfo fieldInfo in fieldInfos)
        {
            EnumModel enumModel = new EnumModel();
            if (!fieldInfo.IsSpecialName)
            {
                enumModel.Name = fieldInfo.Name;
                enumModel.Value = ((T)System.Enum.Parse(type, fieldInfo.Name)).GetHashCode();

                DescriptionAttribute[] enumAttributeList = (DescriptionAttribute[])fieldInfo.GetCustomAttributes(typeof(DescriptionAttribute), false);
                if (enumAttributeList != null && enumAttributeList.Length > 0)
                {
                    enumModel.Description = enumAttributeList[0].Description;
                }
                else
                {
                    enumModel.Description = fieldInfo.Name;
                }
                
                /*
                 * 下面的方法也可以获得枚举的描述
                     dynamic dy = fieldInfo.GetCustomAttributes(typeof(DescriptionAttribute), false);
                     if (dy != null && dy.Length>0)
                     {
                         enumModel.Description = dy[0].Description;
                     }
                     else
                     {
                         enumModel.Description = fieldInfo.Name;
                     }
                */


                listEnumModel.Add(enumModel);
            }
        }
        return listEnumModel;
    }
}
}