我也做了一个,大牛们也帮我看下还能否精简。
<body><div></div><p></p><div></div><p></p><div></div><p></p><div></div><p></p><div></div><p></p>
<img  id="content" src="u=3178436875,1193370616&amp;fm=21&amp;gp=0.jpg"  selfsrc="http://b.zol-img.com.cn/desk/bizhi/image/1/960x600/1354009739228.jpg" />
</body>
</html>
<script>
function offset(ele){
var l=ele.offsetLeft;
var t=ele.offsetTop;
var p=ele.offsetParent;
while(p){
if(window.navigator.userAgent.indexOf("MSIE 8")>-1){
l+=p.offsetLeft;
t+=p.offsetTop;
p=p.offsetParent;
}else{
l+=p.offsetLeft+p.clientLeft;
t+=p.offsetTop+p.clientTop;
p=p.offsetParent;

}
}
return {left:l,top:t}
}
var content=document.getElementById('content');var strSrc="http://b.zol-img.com.cn/desk/bizhi/image/1/960x600/1354009739228.jpg" ;
window.onscroll=function(){
if(!content.loaded)
if(offset(content).top+content.offsetHeight<(document.documentElement.clientHeight||document.body.clientHeight)+(document.documentElement.scrollTop||document.body.scrollTop)){
content.innerHTML='开始的加载------开始加载';
var oImg=new Image();
var oImg=document.createElement('img');
oImg.src="";
oImg.src="loading.gif";//用转圈的图片表示正在下载
//oImg.src=strSrc;
oImg.src=content.getAttribute('selfsrc');
content.loaded='true';
oImg.onload=function(){
content.src=strSrc;
}
}
}