try this
DataTable Dt = new DataTable();
Dt.Columns.Add("Id");
Dt.Columns.Add("Name");
Dt.Rows.Add("0","Stephan");
Dt.Rows.Add("1","Antony");
Dt.Rows.Add("2","Mike");
Dt.DefaultView.Sort = "Name ASC";
combobox1.DataSource = Dt;
combobox1.DisplayMember="Name";
combobox1.ValueMember="Id";