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。
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
不要使用枚举,使用静态类。
取代
private enum PublishStatuses{
NotCompleted,
Completed,
Error
};
with
private static class PublishStatuses{
public static readonly string NotCompleted = "Not Completed";
public static readonly string Completed = "Completed";
public static readonly string Error = "Error";
};
它是这样使用的
PublishStatuses.NotCompleted; // "Not Completed"
使用顶级“扩展方法”解决方案的问题:
私有枚举通常在另一个类中使用。扩展方法解决方案在那里无效,因为它必须在它自己的类中。这个解决方案可以是私有的,并嵌入到另一个类中。
其他回答
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();
}
public enum MyEnum
{
[Description("Option One")]
Option_One
}
public static string ToDescriptionString(this Enum This)
{
Type type = This.GetType();
string name = Enum.GetName(type, This);
MemberInfo member = type.GetMembers()
.Where(w => w.Name == name)
.FirstOrDefault();
DescriptionAttribute attribute = member != null
? member.GetCustomAttributes(true)
.Where(w => w.GetType() == typeof(DescriptionAttribute))
.FirstOrDefault() as DescriptionAttribute
: null;
return attribute != null ? attribute.Description : name;
}
我使用一个泛型类来存储枚举/描述对,并使用一个嵌套的helper类来获取描述。
枚举:
enum Status { Success, Fail, Pending }
泛型类:
注意:由于泛型类不能被枚举约束,我用struct来代替约束,并在构造函数中检查enum。
public class EnumX<T> where T : struct
{
public T Code { get; set; }
public string Description { get; set; }
public EnumX(T code, string desc)
{
if (!typeof(T).IsEnum) throw new NotImplementedException();
Code = code;
Description = desc;
}
public class Helper
{
private List<EnumX<T>> codes;
public Helper(List<EnumX<T>> codes)
{
this.codes = codes;
}
public string GetDescription(T code)
{
EnumX<T> e = codes.Where(c => c.Code.Equals(code)).FirstOrDefault();
return e is null ? "Undefined" : e.Description;
}
}
}
用法:
EnumX<Status>.Helper StatusCodes = new EnumX<Status>.Helper(new List<EnumX<Status>>()
{
new EnumX<Status>(Status.Success,"Operation was successful"),
new EnumX<Status>(Status.Fail,"Operation failed"),
new EnumX<Status>(Status.Pending,"Operation not complete. Please wait...")
});
Console.WriteLine(StatusCodes.GetDescription(Status.Pending));
其他一些避免类/引用类型的更基本的选项:
数组的方法 嵌套结构方法
数组的方法
private struct PublishStatusses
{
public static string[] Desc = {
"Not Completed",
"Completed",
"Error"
};
public enum Id
{
NotCompleted = 0,
Completed,
Error
};
}
使用
string desc = PublishStatusses.Desc[(int)PublishStatusses.Id.Completed];
嵌套结构方法
private struct PublishStatusses
{
public struct NotCompleted
{
public const int Id = 0;
public const string Desc = "Not Completed";
}
public struct Completed
{
public const int Id = 1;
public const string Desc = "Completed";
}
public struct Error
{
public const int Id = 2;
public const string Desc = "Error";
}
}
使用
int id = PublishStatusses.NotCompleted.Id;
string desc = PublishStatusses.NotCompleted.Desc;
更新(03/09/2018)
扩展方法和上面第一种技术的混合。
我更喜欢将枚举定义在它们“所属”的位置(最接近它们的起源源,而不是某个通用的全局名称空间)。
namespace ViewModels
{
public class RecordVM
{
//public enum Enum { Minutes, Hours }
public struct Enum
{
public enum Id { Minutes, Hours }
public static string[] Name = { "Minute(s)", "Hour(s)" };
}
}
}
扩展方法似乎适合于公共区域,枚举的“本地化”定义现在使扩展方法更加详细。
namespace Common
{
public static class EnumExtensions
{
public static string Name(this RecordVM.Enum.Id id)
{
return RecordVM.Enum.Name[(int)id];
}
}
}
枚举及其扩展方法的使用示例。
namespace Views
{
public class RecordView
{
private RecordDataFieldList<string, string> _fieldUnit;
public RecordView()
{
_fieldUnit.List = new IdValueList<string, string>
{
new ListItem<string>((int)RecordVM.Enum.Id.Minutes, RecordVM.Enum.Id.Minutes.Name()),
new ListItem<string>((int)RecordVM.Enum.Id.Hours, RecordVM.Enum.Id.Hours.Name())
};
}
private void Update()
{
RecordVM.Enum.Id eId = DetermineUnit();
_fieldUnit.Input.Text = _fieldUnit.List.SetSelected((int)eId).Value;
}
}
}
注意:我实际上决定消除Enum包装器(和Name数组),因为名称字符串最好来自资源(即配置文件或DB)而不是硬编码,并且因为我最终将扩展方法放在ViewModels名称空间中(只是在不同的“CommonVM.cs”文件中)。此外,整个。id的事情变得令人分心和麻烦。
namespace ViewModels
{
public class RecordVM
{
public enum Enum { Minutes, Hours }
//public struct Enum
//{
// public enum Id { Minutes, Hours }
// public static string[] Name = { "Minute(s)", "Hour(s)" };
//}
}
}
CommonVM.cs
//namespace Common
namespace ViewModels
{
public static class EnumExtensions
{
public static string Name(this RecordVM.Enum id)
{
//return RecordVM.Enum.Name[(int)id];
switch (id)
{
case RecordVM.Enum.Minutes: return "Minute(s)";
case RecordVM.Enum.Hours: return "Hour(s)";
default: return null;
}
}
}
}
枚举及其扩展方法的使用示例。
namespace Views
{
public class RecordView
{
private RecordDataFieldList<string, string> _fieldUnit
public RecordView()
{
_fieldUnit.List = new IdValueList<string, string>
{
new ListItem<string>((int)RecordVM.Enum.Id.Minutes, RecordVM.Enum.Id.Minutes.Name()),
new ListItem<string>((int)RecordVM.Enum.Id.Hours, RecordVM.Enum.Id.Hours.Name())
};
}
private void Update()
{
RecordVM.Enum eId = DetermineUnit();
_fieldUnit.Input.Text = _fieldUnit.List.SetSelected((int)eId).Value;
}
}
}
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!";
}
}
}