dropdownlist 数据绑定显示有问题

1. 1.数据库与dropdownlist控件进行绑定的时候要注意设置dataTextField的值。

 string sql = "select wName from tb_Worker";

            DataTable dt = new DataTable();

            SqlDataAdapter da = new SqlDataAdapter(sql, conn.con);

            da.Fill(dt);

            ddl.DataSource = dt;

            ddl.DataTextField = "wName";

            ddl.DataBind();