<html>
<head></head>
<body>
<div id="ctl00_ContentPlaceHolder1_ctl00_ctl01_Showcase">
<div style="width:100%;text-align:center;"><img src="http://www.xyz.com/aaa.gif" id="ctl00_ContentPlaceHolder1_ctl00_ctl01_loderImg" alt="Loading" /></div> </div>
<script>
q= document.getElementById('ctl00_ContentPlaceHolder1_ctl00_ctl01_Showcase').childNodes[1].getAttribute('src').innerHTML;
alert(q);
</script>
</body>
</html>
我如何访问img标签的'src'属性？我上面的代码它给出了空值,所以什么是错的？
function getH4() {
var xyz = document.getElementsByClassName('bucket_left');
for(var i=0;i<xyz.length;i++){
var x=document.getElementsByTagName("h4")[i].innerHTML;
var current_bucket = xyz[i];
var y=current_bucket.firstChild.href;
var newdiv = document.createElement('div');
newdiv.innerHTML = "<a href=\""+y+"\">"+x+"</a>";
newdiv.className = "hover_title_h4";
current_bucket.appendChild(newdiv);
}
}
window.onscroll=getH4;
在上面的代码中,我想div在div有一个类的s中追加new bucket_left,这div是通过无限滚动生成的.上面的代码工作正常,但在滚动它附加了这么多divs.那么我怎么只追加一次呢？