[c.y.j]js练习表格隔行 添加

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>thead</title>
<script>


function getId(n){
return document.getElementById(n);
}
function lastId(){
return getId("table1").tBodies[0].rows.length+1;
}
function tableColor(){
var otable=getId("table1");
var old="";

for(var i=0;i<lastId()-1;i++){
if(i%2){
otable.tBodies[0].rows[i].style.background="red";
}else{
otable.tBodies[0].rows[i].style.background="green";
}
otable.tBodies[0].rows[i].onmouseover=function(){
old=this.style.background;
this.style.background="blue";
}
otable.tBodies[0].rows[i].onmouseout=function(){
this.style.background=old;
}
}
}
window.onload=function(){
var user=getId("user");
var age=getId("age");
var btn=getId("button");
var otable=getId("table1");
tableColor();
btn.onclick=function(){
var tr=document.createElement("tr");
var td="<td>"+lastId()+"</td><td>"+user.value+"</td><td>"+age.value+"</td>";
tr.innerHTML=td;
otable.tBodies[0].appendChild(tr);
tableColor();
}


}
</script>
</head>


<body>
<input type="text" id="user"/>
<input type="text" id="age" />
<input type="button" id="button" value="add"/>


<table id="table1" border="1">
<thead>
    <th>id</th>
    <th>user</th>
        <th>age</th>
    </thead>
<tbody>
<tr><td>1</td><td>cyj</td><td>24</td></tr>
        <tr><td>2</td><td>cyj</td><td>24</td></tr>
</tbody>
</table>


</body>
</html>