jsp中select的onchange事件用法实例

<script language = "JavaScript"> var onecount; onecount=0; subcat = new Array(); <% int count = 0; java.sql.ResultSet rs1 = DBManage.executeQuery("select hydm,zhydm,zhymc from zhy ");//读取数据 while(rs1.next()) { String selhydm=rs1.getString("hydm").trim(); String zhydm=rs1.getString("zhydm").trim(); String zhymc=rs1.getString("zhymc").trim(); %> subcat[<%=count%>] = new Array("<%=zhydm%>","<%=selhydm%>","<%=zhymc%>");//产生数组 <% count = count + 1; } if(rs1!=null) DBManage.closeCOnn(); %> onecount=<%=count%>; function changelocation(id) { document.form1.selzhy.length = 0; var hydm=id; var i; document.form1.selzhy.options[0] = new Option('选择子行业分类',''); for (i=0;i < onecount; i++) { if (subcat[i][1] == hydm) { document.form1.selzhy.options[document.form1.selzhy.length] = new Option(subcat[i][2], subcat[i][0]); } } } </script> <table cellspacing="0" cellpadding="0"> <tr> <td>选择行业分类:</td> <td> <select onChange="changelocation(document.form1.selhy.options[document.form1.selhy.selectedIndex].value)" size="1" > <option value="2">请选择行业分类</option> <% rs = DBManage.executeQuery("select * from hy"); while(rs.next()) { String hydm=rs.getString("hydm").trim(); String hymc=rs.getString("hymc").trim(); %> <option value="<%=hydm%>"><%=hymc%></option> <% } if(rs!=null) DBManage.closeCOnn(); %> </select> </td> </tr> <tr> <td>选择子行业分类:</td> <td> <select > <option value="" selected>请选择子行业分类</option> </select> </td> </tr> </table> <form name=form1> <select name=province onchange="cityName(this.selectedIndex)"> <option value="">请选择省名</option> </select> <select name=city> <option value="">请选择城名</option> </select> </form> <script language=javascript> var city1 = ["杭州", "宁波", "温州", "绍兴", "金华", "湖州"]; var city2 = ["南京", "苏州", "无锡", "常州", "镇江", "徐州"]; var city3 = ["合肥", "翕县", "黄山", "祁门", "休宁"]; var city4 = ["南昌", "九江", "赣州", "上饶", "新余", "景德镇"]; var provinceName = ["浙江", "江苏", "安徽", "江西"]; function province() { var e = document.form1.province; for (var i=0; i<provinceName.length; i++) e.options.add(new Option(provinceName[i], provinceName[i])); } function cityName(n) { var e = document.form1.city; for (var i=e.options.length; i>0; i--) e.remove(i); if (n == 0) return; var a = eval("city"+ n); //得到城市的数组名 for (var i=0; i<a.length; i++) e.options.add(new Option(a[i], a[i])); } function window.onload() { province(); //初始时给省名下拉菜单赋内容 } </script>