<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<script>
function check_letter(str){
var count=0;
var i=str.length
var count=0;
for(i=0;i<str.length;i++){
substr=str.substring(i,i+1);
var re=/[A-Z]/
if(re.test(substr))
count++;
}
if(count==i){
alert("全部是大写字母");
}
}
</script>
</HEAD>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<script>
function check_letter(str){
var re=/[A-Z]/
if(re.test(str))
alert("含有大写字母");
}
</script>
</HEAD>