/// <summary>

        /// 绑定下拉框

        /// </summary>

        /// <param name="ddl">绑定控件名称</param>

        /// <param name="dt">绑定的数据源</param>

        /// <param name="categoryid">父级id值</param>

        /// <param name="layer">缩进种子</param>

        /// <param name="parentId">父级ID列名</param>

        /// <param name="name">需要显示text列名</param>

        /// <param name="id">需要绑定value的列名</param>

        private void BindChannelType(DropDownList ddl, DataTable dt, string categoryid, int layer, string parentId, string name, string id)

        {

            DataView dv = new DataView(dt);

            dv.RowFilter = parentId + "='" + categoryid + "'";

            //过滤

            if (categoryid != "")

            {

                layer++;

                //默认为第一层

            }

            foreach (DataRowView drv in dv)

            {

                string span = "";

                if (categoryid != "")

                {

                    for (int i = ; i < layer; i++)

                    //父级菜单不缩进

                    {

                        span += "　";

                    }

                }

                ListItem li = new ListItem();

                li.Text = span + drv[name].ToString();

                li.Value = drv[id].ToString();

                ddl.Items.Add(li);

                BindChannelType(ddl, dt, drv[id].ToString(), layer, parentId, name, id);

            }

        }