微信小程序 BASE64 encode 加密 decode 解密

base64.js文件

var Base64 = {

// private property

_keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",

// public method for encoding

encode: function (input) {

var output = "";

var chr1, chr2, chr3, enc1, enc2, enc3, enc4;

var i = 0;

input = Base64._utf8_encode(input);

while (i < input.length) {

chr1 = input.charCodeAt(i++);

chr2 = input.charCodeAt(i++);

chr3 = input.charCodeAt(i++);

enc1 = chr1 >> 2;

enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);

enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);

enc4 = chr3 & 63;

if (isNaN(chr2)) {

enc3 = enc4 = 64;

} else if (isNaN(chr3)) {

enc4 = 64;

}

output = output + this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);

}

return output;

},

// public method for decoding

decode: function (input) {

var output = "";

var chr1, chr2, chr3;

var enc1, enc2, enc3, enc4;

var i = 0;

input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");

while (i < input.length) {

enc1 = this._keyStr.indexOf(input.charAt(i++));

enc2 = this._keyStr.indexOf(input.charAt(i++));

enc3 = this._keyStr.indexOf(input.charAt(i++));

enc4 = this._keyStr.indexOf(input.charAt(i++));

chr1 = (enc1 << 2) | (enc2 >> 4);

chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);

chr3 = ((enc3 & 3) << 6) | enc4;

output = output + String.fromCharCode(chr1);

if (enc3 != 64) {

output = output + String.fromCharCode(chr2);

}

if (enc4 != 64) {

output = output + String.fromCharCode(chr3);

}

}

output = Base64._utf8_decode(output);

return output;

},

// private method for UTF-8 encoding

_utf8_encode: function (string) {

string = string.replace(/\r\n/g, "\n");

var utftext = "";

for (var n = 0; n < string.length; n++) {

var c = string.charCodeAt(n);

if (c < 128) {

utftext += String.fromCharCode(c);

} else if ((c > 127) && (c < 2048)) {

utftext += String.fromCharCode((c >> 6) | 192);

utftext += String.fromCharCode((c & 63) | 128);

} else {

utftext += String.fromCharCode((c >> 12) | 224);

utftext += String.fromCharCode(((c >> 6) & 63) | 128);

utftext += String.fromCharCode((c & 63) | 128);

}

}

return utftext;

},

// private method for UTF-8 decoding

_utf8_decode: function (utftext) {

var string = "";

var i = 0;

var c = 0;

var c1 = 0;

var c2 = 0;

while (i < utftext.length) {

c = utftext.charCodeAt(i);

if (c < 128) {

string += String.fromCharCode(c);

i++;

} else if ((c > 191) && (c < 224)) {

c = utftext.charCodeAt(i + 1);

string += String.fromCharCode(((c & 31) << 6) | (c1 & 63));

i += 2;

} else {

c1 = utftext.charCodeAt(i + 1);

c2 = utftext.charCodeAt(i + 2);

string += String.fromCharCode(((c & 15) << 12) | ((c1 & 63) << 6) | (c2 & 63));

i += 3;

}

}

return string;

}

}

module.exports = Base64

utils文件夹里放入base64.js，微信的js页面调用代码

var base64 = require('../../utils/base64.js')

Page({

data: {

},

onLoad: function () {

var utf8 = base64._utf8_decode("eyJ1c2VySWQiOiI4NDU3NDQxMi1iYmZmLTQyNzEtYjc2Yy01OTgxMjY5ODlmYTciLCJncm91cE5hbWUiOiJZaWJhbmfmma7pgJrlkZjlt6UifQ");

var str = base64.decode(utf8);

console.log(str)

}

})