function findImg() {
var charImg = document.all("chartImg").getElementsByTagName("img");
var imgURLs = "";
for (var i = 0; i < charImg.length; i++) {
var imgPath = getImgPath(charImg[i].src);
var imgNames=getImgNames(imgPath);
if (imgNames!= "vt2.png") {
imgURLs += imgNames; //如果用document.getElementsByTagName("img")[i].src;每取一个图片地址就会对全部图片查找一次，这样效率比较低，还是储存在imgs中比较好！
}
}
alert( imgURLs);
}