如何将sharepoint列表中choice类型的值绑定到dropdownlist上

using (SPSite site=new SPSite(siteurl))
{
using(SPWeb web=site.OpenWeb())
{
try
{
SPList list = web.Lists["ServiecesInfo"];
SPFieldChoice spcustomerlocation = new SPFieldChoice(list.Fields, "CustomerLocation");
for (int i = 0; i < spcustomerlocation.Choices.Count; i++)
{
ddlCustomLocation.Items.Add(new ListItem(spcustomerlocation.Choices[i].ToString(), i.ToString()));
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
}
}