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");

public enum TMyColor
{
  [Description("Red Color")]
  Red,
  [Description("Green Color")]
  Green,
  [Description("Blue Color")]
  Blue
}

To simply get the enum string equivalent (translate value into string):

//----------------------------------------------------------------------------------------
// Get enum string for the specified object.
//----------------------------------------------------------------------------------------
public static string GetEnumString(TMyColorobj)
{
  return Enum.GetName(typeof(TMyColor), obj);
}

To query an enum value for its description:

using System.ComponentModel;
...
 
//----------------------------------------------------------------------------------------
// Get enum description string for the specified object.
//----------------------------------------------------------------------------------------
public static string GetEnumDescription(Enum value)
{
    System.Reflection.FieldInfo fi = value.GetType().GetField(value.ToString());
 
    DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false);
 
    if ((attributes != null) && (attributes.Length > 0))
    {
        return attributes[0].Description;
    }
    else
    {
        return value.ToString();
    }
}

///----------------------------------------------------------------------------------------
/// <summary>
/// Enumerate enums to easily create a drop down list based on an enum.
/// Source: http://blog.spontaneouspublicity.com/post/2008/01/17/Associating-Strings-with-enums-in-C.aspx
/// 
/// Example:
/// DropDownList stateDropDown = new DropDownList();
/// foreach (States state in EnumToList<States>())
/// {
///    stateDropDown.Items.Add(GetEnumDescription(state));
/// }
/// </summary>
/// <typeparam name="T"></typeparam>
/// <returns></returns>
///----------------------------------------------------------------------------------------
public static IEnumerable<T> EnumToList<T>()
{
    Type enumType = typeof(T);
 
    // Can't use generic type constraints on value types,
    // so have to do check like this
    if (enumType.BaseType != typeof(Enum))
    {
        throw new ArgumentException("T must be of type System.Enum");
    }
 
    Array enumValArray  = Enum.GetValues(enumType);
    List<T> enumValList = new List<T>(enumValArray.Length);
 
    foreach (int val in enumValArray)
    {
        enumValList.Add((T)Enum.Parse(enumType, val.ToString()));
    }
 
    return enumValList;
}