OleDbConnection conn = DB.getConnection();//连接数据库
conn.Open();
OleDbDataAdapter odr = new OleDbDataAdapter("select * from product", conn);
DataSet ds = new DataSet();
odr.Fill(ds, "product");
this.DropDownList2.DataSource = ds.Tables["product"].DefaultView;
this.DropDownList2.DataTextField = "title";
this.DropDownList2.DataValueField = "productID";
this.DropDownList2.DataBind();