Home > Web Front-end > JS Tutorial > How to encrypt and decrypt base64

How to encrypt and decrypt base64

php中世界最好的语言
Release: 2018-06-07 13:58:22
Original
3636 people have browsed it

This time I will show you how to encrypt and decrypt base64, and what are the precautions for base64 encryption and decryption. The following is a practical case, let's take a look.

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>js base64加密解密</title>
</head>
<body>
<script>
// 创建Base64对象
var Base64 = {
 _keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
 encode: function(e) {
  var t = "";
  var n, r, i, s, o, u, a;
  var f = 0;
  e = Base64._utf8_encode(e);
  while (f < e.length) {
   n = e.charCodeAt(f++);
   r = e.charCodeAt(f++);
   i = e.charCodeAt(f++);
   s = n >> 2;
   o = (n & 3) << 4 | r >> 4;
   u = (r & 15) << 2 | i >> 6;
   a = i & 63;
   if (isNaN(r)) {
    u = a = 64
   } else if (isNaN(i)) {
    a = 64
   }
   t = t + this._keyStr.charAt(s) + this._keyStr.charAt(o) + this._keyStr.charAt(u) + this._keyStr.charAt(a)
  }
  return t
 },
 decode: function(e) {
  var t = "";
  var n, r, i;
  var s, o, u, a;
  var f = 0;
  e=e.replace(/[^A-Za-z0-9+/=]/g,"");
  while (f < e.length) {
   s = this._keyStr.indexOf(e.charAt(f++));
   o = this._keyStr.indexOf(e.charAt(f++));
   u = this._keyStr.indexOf(e.charAt(f++));
   a = this._keyStr.indexOf(e.charAt(f++));
   n = s << 2 | o >> 4;
   r = (o & 15) << 4 | u >> 2;
   i = (u & 3) << 6 | a;
   t = t + String.fromCharCode(n);
   if (u != 64) {
    t = t + String.fromCharCode(r)
   }
   if (a != 64) {
    t = t + String.fromCharCode(i)
   }
  }
  t = Base64._utf8_decode(t);
  return t
 },
 _utf8_encode: function(e) {
  e = e.replace(/rn/g, "n");
  var t = "";
  for (var n = 0; n < e.length; n++) {
   var r = e.charCodeAt(n);
   if (r < 128) {
    t += String.fromCharCode(r)
   } else if (r > 127 && r < 2048) {
    t += String.fromCharCode(r >> 6 | 192);
    t += String.fromCharCode(r & 63 | 128)
   } else {
    t += String.fromCharCode(r >> 12 | 224);
    t += String.fromCharCode(r >> 6 & 63 | 128);
    t += String.fromCharCode(r & 63 | 128)
   }
  }
  return t
 },
 _utf8_decode: function(e) {
  var t = "";
  var n = 0;
  var r = c1 = c2 = 0;
  while (n < e.length) {
   r = e.charCodeAt(n);
   if (r < 128) {
    t += String.fromCharCode(r);
    n++
   } else if (r > 191 && r < 224) {
    c2 = e.charCodeAt(n + 1);
    t += String.fromCharCode((r & 31) << 6 | c2 & 63);
    n += 2
   } else {
    c2 = e.charCodeAt(n + 1);
    c3 = e.charCodeAt(n + 2);
    t += String.fromCharCode((r & 15) << 12 | (c2 & 63) << 6 | c3 & 63);
    n += 3
   }
  }
  return t
 }
}
// 定义字符串
var string = &#39;Hello World!&#39;;
// 加密
var encodedString = Base64.encode(string);
console.log(encodedString); // 输出: "SGVsbG8gV29ybGQh"
// 解密
var decodedString = Base64.decode(encodedString);
console.log(decodedString); // 输出: "Hello World!"
</script>
</body>
</html>
Copy after login

Run results:

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the php Chinese website!

Recommended reading:

JS implementation of gray text prompts in the input box

react redux from scratch

The above is the detailed content of How to encrypt and decrypt base64. For more information, please follow other related articles on the PHP Chinese website!

Related labels:
source:php.cn
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Popular Tutorials
More>
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template