代码；
<html>
<head>
<title>js标签属性的添加</title>
<script >
function setxxx(){
alert("xx");
var box = document.getElementById("box");
var oLi = document.createElement("li");
var oH3 = document.createElement("h3");
oH3.innerHTML = "这是js生成的一个h3的标签";
oH3.style.height="30px";
oH3.style.background = "red";
oH3.setAttribute('class','dtime');
box.appendChild(oH3); } </script>
</head>
<div id="box">
<input type="button" value="点击" onclick="setxxx()" />
</div> <body> </body> </html>
截图:
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