<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>字元串對象</title>
</head>
<body>
</body>
</html>
<script>
var str = 'abcdABCD EFGefg';
len = str.length;
console.log(len)
console.log(str.indexOf('a'))
console.log(str.match('f'))
console.log(str.replace('abc','123'))
</script>