绑定下拉框

 public void DropDownListBinding(DropDownList DDList, string sql, string strText, string strField, string str_qxz)
    {

        DataTable dt = MDGL.DBUtility.SQLServerHelper.GetDataTable(CommandType.Text, sql);
        DDList.DataSource = dt;

        DDList.DataValueField = strField;
        DDList.DataTextField = strText;
        DDList.DataBind();
        ListItem NewItem = new ListItem();
        NewItem.Value = "";
        NewItem.Text = str_qxz;
        DDList.Items.Insert(0, NewItem);
    }