我的枚举由以下值组成:

private enum PublishStatusses{
    NotCompleted,
    Completed,
    Error
};

我希望能够以用户友好的方式输出这些值。 我不需要再从字符串到值。


当前回答

这是对Ray Booysen的代码的更新,使用通用的GetCustomAttributes方法和LINQ使事情变得更整洁。

    /// <summary>
    /// Gets the value of the <see cref="T:System.ComponentModel.DescriptionAttribute"/> on an struct, including enums.  
    /// </summary>
    /// <typeparam name="T">The type of the struct.</typeparam>
    /// <param name="enumerationValue">A value of type <see cref="T:System.Enum"/></param>
    /// <returns>If the struct has a Description attribute, this method returns the description.  Otherwise it just calls ToString() on the struct.</returns>
    /// <remarks>Based on http://stackoverflow.com/questions/479410/enum-tostring/479417#479417, but useful for any struct.</remarks>
    public static string GetDescription<T>(this T enumerationValue) where T : struct
    {
        return enumerationValue.GetType().GetMember(enumerationValue.ToString())
                .SelectMany(mi => mi.GetCustomAttributes<DescriptionAttribute>(false),
                    (mi, ca) => ca.Description)
                .FirstOrDefault() ?? enumerationValue.ToString();
    }   

其他回答

你可以使用Humanizer包人性化枚举的可能性。一个eaxample:

enum PublishStatusses
{
    [Description("Custom description")]
    NotCompleted,
    AlmostCompleted,
    Error
};

然后你可以直接在enum上使用Humanize扩展方法:

var st1 = PublishStatusses.NotCompleted;
var str1 = st1.Humanize(); // will result in Custom description

var st2 = PublishStatusses.AlmostCompleted;
var str2 = st2.Humanize(); // will result in Almost completed (calculated automaticaly)

这是对Ray Booysen的代码的更新,使用通用的GetCustomAttributes方法和LINQ使事情变得更整洁。

    /// <summary>
    /// Gets the value of the <see cref="T:System.ComponentModel.DescriptionAttribute"/> on an struct, including enums.  
    /// </summary>
    /// <typeparam name="T">The type of the struct.</typeparam>
    /// <param name="enumerationValue">A value of type <see cref="T:System.Enum"/></param>
    /// <returns>If the struct has a Description attribute, this method returns the description.  Otherwise it just calls ToString() on the struct.</returns>
    /// <remarks>Based on http://stackoverflow.com/questions/479410/enum-tostring/479417#479417, but useful for any struct.</remarks>
    public static string GetDescription<T>(this T enumerationValue) where T : struct
    {
        return enumerationValue.GetType().GetMember(enumerationValue.ToString())
                .SelectMany(mi => mi.GetCustomAttributes<DescriptionAttribute>(false),
                    (mi, ca) => ca.Description)
                .FirstOrDefault() ?? enumerationValue.ToString();
    }   

我使用系统中的Description属性。ComponentModel名称空间。简单地装饰enum:

private enum PublishStatusValue
{
    [Description("Not Completed")]
    NotCompleted,
    Completed,
    Error
};

然后使用下面的代码来检索它:

public static string GetDescription<T>(this T enumerationValue)
    where T : struct
{
    Type type = enumerationValue.GetType();
    if (!type.IsEnum)
    {
        throw new ArgumentException("EnumerationValue must be of Enum type", "enumerationValue");
    }

    //Tries to find a DescriptionAttribute for a potential friendly name
    //for the enum
    MemberInfo[] memberInfo = type.GetMember(enumerationValue.ToString());
    if (memberInfo != null && memberInfo.Length > 0)
    {
        object[] attrs = memberInfo[0].GetCustomAttributes(typeof(DescriptionAttribute), false);

        if (attrs != null && attrs.Length > 0)
        {
            //Pull out the description value
            return ((DescriptionAttribute)attrs[0]).Description;
        }
    }
    //If we have no description attribute, just return the ToString of the enum
    return enumerationValue.ToString();
}

我用扩展方法做到这一点:

public enum ErrorLevel
{
  None,
  Low,
  High,
  SoylentGreen
}

public static class ErrorLevelExtensions
{
  public static string ToFriendlyString(this ErrorLevel me)
  {
    switch(me)
    {
      case ErrorLevel.None:
        return "Everything is OK";
      case ErrorLevel.Low:
        return "SNAFU, if you know what I mean.";
      case ErrorLevel.High:
        return "Reaching TARFU levels";
      case ErrorLevel.SoylentGreen:
        return "ITS PEOPLE!!!!";
      default:
        return "Get your damn dirty hands off me you FILTHY APE!";
    }
  }
}

另一篇文章是Java。在c#中,你不能把方法放在枚举中。

就像这样做:

PublishStatusses status = ...
String s = status.ToString();

如果您想为枚举值使用不同的显示值,您可以使用Attributes和Reflection。