如何向Enum添加多个属性？

Question

我有一个SQL查询表称为ClientCreditResolutionPlanActionType,我想转换为枚举在C# .

非常基本的要求,对吗？对.

然而,我的表,现在枚举,有几列,或者现在,需要使用它的描述属性:

• StatusIcon
• 状态文本
• 的TypeText

---

所以我想我能做到......

namespace System.ComponentModel
{
    class StatusIconAttribute : Attribute
    {
        public string StatusIcon;
        public StatusIconAttribute(string statusIcon) { StatusIcon = statusIcon; }
    }

    class StatusTextAttribute : Attribute
    {
        public string StatusText;
        public StatusTextAttribute(string statusText) { StatusText = statusText; }
    }

    class TypeTextAttribute : Attribute
    {
        public string TypeText;
        public TypeTextAttribute(string typeText) { TypeText = typeText; }
    }
}

...在我的Extensions.cs课程中......

public static class EnumExtensions
{
    public static string GetStatusIcon(this Enum value)
    {
        var type = value.GetType();

        string name = Enum.GetName(type, value);              
        if (name == null) { return null; }

        var field = type.GetField(name);
        if (field == null) { return null; }

        var attr = Attribute.GetCustomAttribute(field, typeof(StatusIconAttribute)) as StatusIconAttribute;
        if (attr == null) { return null; }

        return attr.StatusIcon;
    }

    public static string GetStatusText(this Enum value)
    {
        var type = value.GetType();

        string name = Enum.GetName(type, value);              
        if (name == null) { return null; }

        var field = type.GetField(name);
        if (field == null) { return null; }

        var attr = Attribute.GetCustomAttribute(field, typeof(StatusTextAttribute)) as StatusTextAttribute;
        if (attr == null) { return null; }

        return attr.StatusText;
    }

    public static string GetTypeText(this Enum value)
    {
        var type = value.GetType();
        string name = Enum.GetName(type, value);              

        var type = value.GetType();

        string name = Enum.GetName(type, value);              
        if (name == null) { return null; }

        var field = type.GetField(name);
        if (field == null) { return null; }

        var attr = Attribute.GetCustomAttribute(field, typeof(TypeTextAttribute)) as TypeTextAttribute;
       if (attr == null) { return null; }

        return attr.TypeText;
    }
}

...最后在我的其他项目中使用它:

namespace ClientSystemServiceLibrary.Enums
{
    [DataContract]
    public enum ClientCreditResolutionPlanActionType
    {
        [EnumMember]
        [TypeText("New resolution plan submitted.")]
        [StatusText("New Plan")]
        [StatusIcon("star.png")]
        NewPlan = 1,

        [EnumMember]
        [TypeText("Resolution plan waiting on approval.")]
        [StatusText("Under Review")]
        [StatusIcon("review.png")]
        UnderReview = 2,

        [EnumMember]
        [TypeText("Resolution plan approved.")]
        [StatusText("Approved")]
        [StatusIcon("check.png")]
        Approved = 3,

        [EnumMember]
        [TypeText("Resolution plan rejected.")]
        [StatusText("Rejected")]
        [StatusIcon("cross.png")]
        Rejected = 4,

        [EnumMember]
        [TypeText("New resolution plan comment submitted.")]
        [StatusText("New Comment")]
        [StatusIcon("message.png")]
        NewComment = 5
    }
}E

除了,我认为是错的,因为我收到这些错误消息:

由于其保护级别,"System.CompenentModel.TypeTextAttribute"无法访问

和

找不到类型或命名空间名称'TypeText'(您是否缺少using指令或程序集引用？)

同样......对于所有3.

Answer 1

默认情况下,所有类都是内部的.如果希望可以从其他程序集访问它们,则应指定"public"访问修饰符.像这样:

public class TypeTextAttribute : Attribute
{
    public string TypeText;
    public TypeTextAttribute(string typeText) { TypeText = typeText; }
}