JS页面内查找

<script language="JavaScript">
var NS4 = (document.layers);    // Which browser?
        var IE4 = (document.all);
var win = window;    // window to search.
        var n   = 0;
function findInPage(str) {
var txt, i, found;
if (str == "")
return false;
if (NS4) {
if (!win.find(str))
while(win.find(str, false, true))
n++;
else
n++;
if (n == 0)
alert("Not found.");
}
if (IE4) {
txt = win.document.body.createTextRange();
for (i = 0; i <= n && (found = txt.findText(str)) != false; i++) {
txt.moveStart("character", 1);
txt.moveEnd("textedit");
}
if (found) {
txt.moveStart("character", -1);
txt.findText(str);
txt.select();
txt.scrollIntoView();
n++;
}
else {
if (n > 0) {
n = 0;
findInPage(str);
}
}
}
return false;
}
</script>