<html>
<head>
<script>
var txt="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
document.write("这串字符的长度是:"+txt.length);
</script>
</head>
<body>
</body>
分类
<html>
<head>
<script>
var txt="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
document.write("这串字符的长度是:"+txt.length);
</script>
</head>
<body>
</body>