console 命令行工具 X clear

console

<!DOCTYPE html> 
<html>
<head>
    <meta charset="utf-8" />
    <title></title>
    <script>
        var str ="Rome was not built in a day";
        arr =str.replace(/\s/g);//去掉空格
        var sum =0;
        for(var i of str)
        {
            sum++;
        }
        document.write("字符个数为："+sum);
    </script>
</head>
<body>
</body>
</html>