To declare an enumerated type:

public enum TMyColor
{
  Red,
  Green,
  Blue
}

To convert an enum value to string:

public string GetEnumString(TMyColor obj)
{
     return Enum.GetName(typeof(TMyColor), obj);
}

To convert a string into an enum:

TMyColor mycolor = (TMyColor)Enum.Parse(typeof(TMyColor), "Red");