如何通过 MVC Razor 代码获取枚举成员的显示名称属性？

小编典典

如何通过 MVC Razor 代码获取枚举成员的显示名称属性？

all

我的模型中有一个属性，称为Promotion它的类型是一个标志枚举，称为UserPromotion. 我的枚举成员的显示属性设置如下：

[Flags]
public enum UserPromotion
{
    None = 0x0,

    [Display(Name = "Send Job Offers By Mail")]
    SendJobOffersByMail = 0x1,

    [Display(Name = "Send Job Offers By Sms")]
    SendJobOffersBySms = 0x2,

    [Display(Name = "Send Other Stuff By Sms")]
    SendPromotionalBySms = 0x4,

    [Display(Name = "Send Other Stuff By Mail")]
    SendPromotionalByMail = 0x8
}

现在我希望能够在我的视图中创建say a来显示我的属性ul的选定值。Promotion这是我到目前为止所做的，但问题是我怎样才能在这里获得显示名称？

<ul>
    @foreach (int aPromotion in @Enum.GetValues(typeof(UserPromotion)))
    {
        var currentPromotion = (int)Model.JobSeeker.Promotion;
        if ((currentPromotion & aPromotion) == aPromotion)
        {
        <li>Here I don't know how to get the display attribute of "currentPromotion".</li>
        }
    }
</ul>

阅读 85

2022-05-20

共1个答案

小编典典

更新

第一个解决方案的重点是从枚举中获取显示名称。下面的代码应该是您问题的确切解决方案。

您可以将此辅助类用于枚举：

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Reflection;

public static class EnumHelper<T>
    where T : struct, Enum // This constraint requires C# 7.3 or later.
{
    public static IList<T> GetValues(Enum value)
    {
        var enumValues = new List<T>();

        foreach (FieldInfo fi in value.GetType().GetFields(BindingFlags.Static | BindingFlags.Public))
        {
            enumValues.Add((T)Enum.Parse(value.GetType(), fi.Name, false));
        }
        return enumValues;
    }

    public static T Parse(string value)
    {
        return (T)Enum.Parse(typeof(T), value, true);
    }

    public static IList<string> GetNames(Enum value)
    {
        return value.GetType().GetFields(BindingFlags.Static | BindingFlags.Public).Select(fi => fi.Name).ToList();
    }

    public static IList<string> GetDisplayValues(Enum value)
    {
        return GetNames(value).Select(obj => GetDisplayValue(Parse(obj))).ToList();
    }

    private static string lookupResource(Type resourceManagerProvider, string resourceKey)
    {
        var resourceKeyProperty = resourceManagerProvider.GetProperty(resourceKey,
            BindingFlags.Static | BindingFlags.Public, null, typeof(string),
            new Type[0], null);
        if (resourceKeyProperty != null)
        {
            return (string)resourceKeyProperty.GetMethod.Invoke(null, null);
        }

        return resourceKey; // Fallback with the key name
    }

    public static string GetDisplayValue(T value)
    {
        var fieldInfo = value.GetType().GetField(value.ToString());

        var descriptionAttributes = fieldInfo.GetCustomAttributes(
            typeof(DisplayAttribute), false) as DisplayAttribute[];

        if (descriptionAttributes[0].ResourceType != null)
            return lookupResource(descriptionAttributes[0].ResourceType, descriptionAttributes[0].Name);

        if (descriptionAttributes == null) return string.Empty;
        return (descriptionAttributes.Length > 0) ? descriptionAttributes[0].Name : value.ToString();
    }
}

然后你可以在你的视图中使用它，如下所示：

<ul>
    @foreach (var value in @EnumHelper<UserPromotion>.GetValues(UserPromotion.None))
    {
         if (value == Model.JobSeeker.Promotion)
        {
            var description = EnumHelper<UserPromotion>.GetDisplayValue(value);
            <li>@Html.DisplayFor(e => description )</li>
        }
    }
</ul>

希望能帮助到你！:)

2022-05-20