求助HTML高手radio如何响应失去选中事件_html/css_WEB-ITnose
呵呵~！
我做的东西比较恶心
现在遇到了个问题就是input的radio控件响应事件问题
是这样：一个radio不光要响应被选中的事件，还要监听自己被撤销选中的事件
比如我有个选择题，A，B，C三个选项
用户在页面先选了A，根据某些业务逻辑，选了A以后是要进行一些相关操作的
但是这时候用户想了一下，觉得选A不好，改选B了
那么刚才根据用户选了A这一结果执行的操作，就要实现逆操作
我想设置radio的 onpropertychange事件来实现这个操作，但是发现把JavaScript方法注册到事件上以后
用户点中radio的时候，浏览器调用了2次该方法
而且似乎是在radio的checked属性被设置为true之前调用一次，设置为true之后调用一次
而当选了同组其他radio的时候，这个方法只执行了一次
很郁闷
所以来问问
有没有方法监听radio控件被选中和被撤销的事件啊？
谢谢大家了
回复讨论(解决方案)
换个思路。如果改选B，那么会触发事件。这样同样可以监听A撤消啊
试试 onclick
用一个全局变量记住当前选项
<html> <script language="javascript" defer="defer"> var cur;function check(){ var val; var rds = document.forms[0].rd; for(var i=0;i<rds.length;i++){ if(rds[i].checked){ val = i; break; } } if(val != cur){cur = val; alert("changed")}} window.onload=function(){ var rds = document.forms[0].rd; for(var i=0;i<rds.length;i++){ if(rds[i].checked){ cur = i; break; } }}</script> <body><form><input type="radio" name="rd" value="0" checked="checked" onclick="check()"> 0<br><input type="radio" name="rd" value="1" onclick="check()"> 1<br><input type="radio" name="rd" value="2" onclick="check()"> 2<br></form></body> </html>
<div id=radios> a <input type=radio name=a value=a > b <input type=radio name=a value=b> c <input type=radio name=a value=c></div><script language="javascript"><!--var obj=document.getElementById("radios").getElementsByTagName("input")for (var i=0;i<obj.length;i++){(function(k){obj[i].onclick=function(){cha(k)}})(i)}var lastChecked=nullfunction cha(k){if (lastChecked==k)returnif (lastChecked!=null){ //处理obj[lastChecked] alert("上次选中："+lastChecked)}lastChecked=k//处理obj[lastChecked]alert("本次选中："+lastChecked)}//--></script> 使用临时变量是不行的
因为页面上的选择题的数量，以及选择题和填空题
以及题目之间的跳转关系
比如：单选某一选项要跳转到哪个题
选择题之间选项的组合，选择题与填空题之间的组合
等等都是用户在设计试卷的时候指定的
不是写死在页面上的
变量可以动态创建，或用数组，不需要写死。
路过 学习
用一个全局变量记住当前选项
HTML code
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