So, you have an enum defined as follows:
public enum Gender
{
Male= 0,
Female= 1
}
Code to Bind the Dropdown
string[] names = Enum.GetNames(typeof(Gender));
var values = (Gender[])Enum.GetValues(typeof(Gender));
for (int i = 0; i < names.Length; i++)
{
DdlGender.Items.Add(new ListItem(names[i], values[i].ToString()));
}