(oracle+c#)DropDownList绑定数据源后,新增默认空item

dropdownlist

绑定数据源后,添加一行空值,并且是默认选择空值

 void init_company()
        {
            string commstr = "select * from base_company_test";
            OracleConnection conn = new OracleConnection(connstr);
            OracleCommand comm = new OracleCommand(commstr, conn);
            conn.Open();

            company.DataSource = comm.ExecuteReader();
            company.DataTextField = "com_name";
            company.DataValueField = "com_id";
            company.DataBind();
            conn.Close();
            company.Items.Insert(0, new ListItem("", ""));
       }