Data Formatting for DataTextFormatString field for dropdownlist in asp.net

int ID = convert.ToInt32(ddl.SelectedItem.Value)

tblEntities Entities = new tblEntities();

ddl.DataSource = Entities.widget.Where(p => p.MID == ID).ToList();

ddl.DataTextField = "ID";

ddl.DataValueField = "ID";        

ddl.DataTextFormatString = "Widget - " + "{0}"; <------ Formatted Text

ddl.DataBind();

ddl.Items.Insert(0, new ListItem("--Select--", "-1"));