<asp:DropDownList ID="type1" runat="server" CssClass="tfont" onchange="link(this.id);" </asp:DropDownList> <%-- 大小类--%> <script> function link(id) { var obj = document.getElementById(id); var obj1 = document.getElementById('type2'); var name = ""; for(i = 0 ; i < obj.options.length ; i++ ) { if(obj.options[i].selected) { name = obj.options[i].value; } } var names = bargain_class.link(name).value.split(','); var obj1_count = obj1.options.length for (i = 0 ; i < obj1_count ; i++) { obj1.options.remove(0); } for (i = 0 ; i < names.length ; i ++ ) { option1 = document.createElement("option"); option1.innerHTML = names[i]; obj1.appendChild(option1); } // alert(names); } </script> //后台代码 AjaxPro.Utility.RegisterTypeForAjax(typeof(bargain_class)); //本页页面名 //===============================ajax调用===================================== [AjaxPro.AjaxMethod] public string link(string name) { string text = ""; string sql = "select name from Management_products_class where pid='" + name + "'"; DataTable dt = LinkSql.conn(sql); for (int i = 0; i < dt.Rows.Count; i++) { if (text == "") { text = dt.Rows[i]["name"].ToString(); } else { text += "," + dt.Rows[i]["name"].ToString(); } } return text; }