C# A method that will accept any List<enum> and return a string array

There is an incredibly longer story to why I’m actually doing this, so I’m sure there is a better way as an overall approach. I don’t have time to refactor the entire base structure and I want to minimize about 20k lines in the library to a method. What I want to be able to do is take any List<Enum> and return a string[]. My example is below, I’m sure I’m probably missing some sort of reflection. Thanks!

public enum ActivityEnum
    {
        ID,
        ACTIVITYTYPEID,
        CAMPAIGNID,
        BUDGETID,
        LISTID
    }


public enum ActivityAttributeEnum
    {
        ID,
        ACTIVITYID,
        ACTIVITYATTRIBUTE,
        ENABLED,
        CREATEDBY,
        CREATEDDATE,
        LASTUPDATEBY,
        LASTUPDATEDATE
    }


public string[] myStrings(List<activtyEnum> activityEnums)
        {
            var array = new string[activityEnums.Count];
            for (int i = 0; i < activityEnums.Count; i++)
                array[i] = activityEnums[i].ToString();

            return array;

        }

What I’m unsure of is how to accept any enum. In my example I have activityEnum, but I want the method to accept both ActivityAttribtueEnum and ActivityEnum. There are about 600 enums, so a generic way would be great.

Thanks!

>Solution :

private string[] GetNames<TEnum>(List<TEnum> enums) where TEnum : Enum
{
    return enums.Select(e => e.ToString()).ToArray();
}

You really ought to declare the parameter as type IEnumerable<TEnum> because that will work with a List<T>, an array, the result of a LINQ query and various other list types too.

Note that any list can have its items converted to a string array in this way too, so there’s not really a need to to constrain the item type to be an enum. It won’t actually hurt to define the method without a generic constraint. You might just want to change the name in that case, because the values returned might not be names.