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javascript

解决方案 »

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<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title><script type="text/javascript">
function init(){
var trs= document.getElementsByTagName("tr");
for(var i = 1 ; i<trs.length ; i++){
if(i%2==0){
trs[i].onmouseover = function(){
this.style.background = "red";
}
}
}
}
</script>
</head><body onLoad="init()">
     <table width="98%" border="1" cellspacing="0" cellpadding="0">
  <tr>
    <th scope="col">asdfsadf</th>
    <th scope="col">sadf</th>
  </tr>
  <tr>
    <td>asdf</td>
    <td>asdf</td>
  </tr>
  <tr>
    <td>asdf</td>
    <td>sadfdf</td>
  </tr>
</table><script></script>
</body></html>
补充一下一楼，<!doctype html>
<html>
<head>
    <meta charset="utf-8">
    <title>无标题文档</title>    <script type="text/javascript">
        function init(){
            var trs = document.getElementsByTagName("tr");
            var old = '';
            for(var i = 1; i < trs.length; i++){
                trs[i].style.background = "#fff";
                if(i % 2 == 0){
                    trs[i].style.background = "#f1f1f1";
                }
                trs[i].onmouseover = function(){
                    old = this.style.background;
                    this.style.background = "#f00";
                }
                trs[i].onmouseout = function(){
                    this.style.background = old;
                }
            }
        }
    </script>
</head><body onLoad="init()">
<table width="98%" border="1" cellspacing="0" cellpadding="0">
    <tr>
        <th scope="col">asdfsadf</th>
        <th scope="col">sadf</th>
    </tr>
    <tr>
        <td>asdf</td>
        <td>asdf</td>
    </tr>
    <tr>
        <td>asdf</td>
        <td>sadfdf</td>
    </tr>
    <tr>
        <td>asdf</td>
        <td>asdf</td>
    </tr>
    <tr>
        <td>asdf</td>
        <td>sadfdf</td>
    </tr>
    <tr>
        <td>asdf</td>
        <td>asdf</td>
    </tr>
    <tr>
        <td>asdf</td>
        <td>sadfdf</td>
    </tr>
</table>
</body>
</html>