https://blog.csdn.net/weixin_42193179/article/details/104932315
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<title>js Base64.encode(str)_decode(str)</title>
<script src="./lib/base64.js"></script>
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<script>
/*参考：https://www.jianshu.com/p/14437764eff3*/
// 1.开源的 base64.js: https://github.com/dankogai/js-base64
let s1 = 'china is so nb';
let s2 = Base64.encode(s1); // 编码
console.log("s2:", s2);
// s2: Y2hpbmEgaXMgc28gbmI=
let s3 = Base64.decode(s2); // 解码
console.log("s3:", s3);
// s3: china is so nb
// 2.浏览器提供了原生的 Base64编码、解码方法
let s4 = window.btoa(s1); // 编码
console.log("
s4:", s4);
//s4: Y2hpbmEgaXMgc28gbmI=
let s5 = window.atob("Y2hpbmEgaXMgc28gbmI="); // 解码
console.log("s5:", s5);
// s5: china is so nb
</script>
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