<body onload="a()">
<script>
function a()
{
for(i=0;i<document.images.length;i++) alert(document.images[i].src)
}
</script>
<script>
function a()
{
for(i=0;i<document.images.length;i++) alert(document.images[i].src)
}
</script>
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<br><img border=0 src=http://expert.csdn.net/images/csdn.gif><script language=javascript>
for (var i=0; i<document.images.length; i++)
alert(document.images[i].src);
</script>
<script>
function a()
{
l = document.getElementsByTagName("IMG")
for(i=0;i<l.length;i++) alert(l[i].src)
}
</script>