代码如下: if (!IsPostBack) { //一级分类列表 this.DropDownList1.DataSource = dsbb.SelectSubjct1(); this.DropDownList1.DataTextField = “cName”; this.DropDownList1.DataValueField = “Ccode”; this.DropDownList1.DataBind(); this.DropDownList1.Items.Insert(0,new List