We can bind the enum to a dropdown as follows
public enum Colors
{
Red = 1,
Orange = 2,
Green = 3,
Black = 4,
None = 0
}
and to add this to a dropdown you can do as on page load
foreach(int val in Enum.GetValues(typeof(Colors)))
{
ddlcolors.Items.Add(new ListItem(Enum.GetName(typeof(Colors), val)))
}