<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
body {
font-family: "Microsoft YaHei", serif;
}
body, dl, dd, p, h1, h2, h3, h4, h5, h6 {
margin: 0;
}
ol, ul, li {
margin: 0;
padding: 0;
list-style: none;
}
img {
border: none
}
</style>
</head>
<body>
<div id="wrap"></div>
<script>
let str = "菜鸟联盟123";
let s = "ABCabc";
let data = "2020-2-12";
console.log(str.length);
console.log(str[3]); //低版本ie不兼容
console.log(str.charAt(3)); //所有浏览器都兼容
console.log(str.charCodeAt(3)); //字符串对应编码
console.log(String.fromCharCode(12313)); //编码对应的字符
console.log(str.substring(1, 3)); //截取 左闭右开
console.log(s.toUpperCase()); //全部变大写
console.log(s.toLowerCase()); //全部变小写
console.log(s.toLocaleUpperCase()); //全部变大写
console.log(s.toLocaleLowerCase()); //全部变小写
console.log(data.split("-")); //用什么符号分隔开
</script>
</body>
</html>
Python3Turtle