Associating enums with strings in C#


Question

I know the following is not possible because it has to be an int

enum GroupTypes
{
    TheGroup = "OEM",
    TheOtherGroup = "CMB"
}

From my database I get a field with incomprehensive codes (the OEM and CMB's). I would want to make this field into an enum or something else understandable. Because the target is readability the solution should be terse.
What other options do I have?

1
281
3/21/2010 10:28:57 AM

Accepted Answer

I like to use properties in a class instead of methods, since they look more enum-like.

Here's a example for a Logger:

public class LogCategory
{
 private LogCategory(string value) { Value = value; }

 public string Value { get; set; }

 public static LogCategory Trace { get { return new LogCategory("Trace"); } }
 public static LogCategory Debug { get { return new LogCategory("Debug"); } }
 public static LogCategory Info { get { return new LogCategory("Info"); } }
 public static LogCategory Warning { get { return new LogCategory("Warning"); } }
 public static LogCategory Error { get { return new LogCategory("Error"); } }
}

Pass in type-safe string values as a parameter:

public static void Write(string message, LogCategory logCategory)
{
   var log = new LogEntry { Message = message };
   Logger.Write(log, logCategory.Value);
}

Usage:

Logger.Write("This is almost like an enum.", LogCategory.Info);
313
8/27/2009 8:12:41 PM

You could also use the extension model:

public enum MyEnum
{
    [Description("String 1")]
    V1= 1,
    [Description("String 2")]
    V2= 2
} 

Your Extension Class

public static class MyEnumExtensions
{
    public static string ToDescriptionString(this MyEnum val)
    {
        DescriptionAttribute[] attributes = (DescriptionAttribute[])val
           .GetType()
           .GetField(val.ToString())
           .GetCustomAttributes(typeof(DescriptionAttribute), false);
        return attributes.Length > 0 ? attributes[0].Description : string.Empty;
    }
} 

usage:

MyEnum myLocal = MyEnum.V1;
print(myLocal.ToDescriptionString());

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