日期:2014-05-16 浏览次数:20346 次
<html> <title>考试申请</title> <head> </head> <body> <select id="selterm" onChange="changeterm()" style="width:100px"> <option>选择学期</option> </select> <select id="selclass" style="width:100px"> <option>选择课程</option> </select> <script type="text/javascript"> var termlist = []; termlist['第一学期'] = ["c#","计算机基础","电子商务概论"]; termlist['第二学期'] = ["dreameaver","市场营销","网络","asp"]; var tmp = []; var obj1 = document.getElementById('selterm'); var obj2 = document.getElementById('selclass'); for(var x in termlist){ obj1.add(new Option(x, null)); tmp.push(x); } function changeterm(){ var l = termlist[tmp[obj1.selectedIndex - 1]]; obj2.length = 1; for(var i = 0, len = l.length; i< len; i++){ obj2.add(new Option(l[i], null)); } } </script> </body> </html>
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<html> <title>考试申请</title> <head> <script type="text/javascript"> var termlist = new Array(); termlist['第一学期'] = ["c#","计算机基础","电子商务概论"]; termlist['第二学期'] = ["dreameaver","市场营销","网络","asp"]; function changeterm() { var term = document.getElementById('selterm').value; var cls = document.getElementById('selclass'); //class是Javascript语言保留字,不能用作变量名 cls.options.length = 0; for (var i in termlist) { if (i == term) { for(var j in termlist[i]) cls.options.add(new Option(termlist[i][j], termlist[i][j])); } } } window.onload = function() { var obj = document.getElementById('selterm'); for(var i in termlist) obj.options.add(new Option(i, i)); } </script> </head> <body> <select id="selterm" onChange="changeterm()" style="width:100px"> <option>选择学期</option> </select> <select id="selclass" style="width:100px"> <option>选择课程</option> </select> </body> </html>