微信小程序中使用Base64编码解码
时间:2023-02-11
//创建js - base64.js文件 (function(global) { 'use strict'; var global = global || {}; var _Base64 = global.Base64; var version = "1.0.0"; var buffer; var b64chars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'; var b64tab = function(bin) { var t = {}; for (var i = 0, l = bin.length; i < l; i++) t[bin.charAt(i)] = i; return t; } (b64chars); var fromCharCode = String.fromCharCode; // encoder stuff var cb_utob = function(c) { if (c.length < 2) { var cc = c.charCodeAt(0); return cc < 0x80 ? c: cc < 0x800 ? (fromCharCode(0xc0 | (cc >>> 6)) + fromCharCode(0x80 | (cc & 0x3f))) : (fromCharCode(0xe0 | ((cc >>> 12) & 0x0f)) + fromCharCode(0x80 | ((cc >>> 6) & 0x3f)) + fromCharCode(0x80 | (cc & 0x3f))); } else { var cc = 0x10000 + (c.charCodeAt(0) - 0xD800) * 0x400 + (c.charCodeAt(1) - 0xDC00); return (fromCharCode(0xf0 | ((cc >>> 18) & 0x07)) + fromCharCode(0x80 | ((cc >>> 12) & 0x3f)) + fromCharCode(0x80 | ((cc >>> 6) & 0x3f)) + fromCharCode(0x80 | (cc & 0x3f))); } }; var re_utob = /[\uD800-\uDBFF][\uDC00-\uDFFFF]|[^\x00-\x7F]/g; var utob = function(u) { return u.replace(re_utob, cb_utob); }; var cb_encode = function(ccc) { var padlen = [0, 2, 1][ccc.length % 3], ord = ccc.charCodeAt(0) << 16 | ((ccc.length > 1 ? ccc.charCodeAt(1) : 0) << 8) | ((ccc.length > 2 ? ccc.charCodeAt(2) : 0)), chars = [b64chars.charAt(ord >>> 18), b64chars.charAt((ord >>> 12) & 63), padlen >= 2 ? '=': b64chars.charAt((ord >>> 6) & 63), padlen >= 1 ? '=': b64chars.charAt(ord & 63)]; return chars.join(''); }; var btoa = global.btoa ? function(b) { return global.btoa(b); }: function(b) { return b.replace(/[\s\S]{1,3}/g, cb_encode); }; var _encode = buffer ? function(u) { return (u.constructor === buffer.constructor ? u: new buffer(u)).toString('base64') }: function(u) { return btoa(utob(u)) }; var encode = function(u, urisafe) { return ! urisafe ? _encode(String(u)) : _encode(String(u)).replace(/[+\/]/g, function(m0) { return m0 == '+' ? '-': '_'; }).replace(/=/g, ''); }; var encodeURI = function(u) { return encode(u, true) }; // decoder stuff var re_btou = new RegExp([ '[\xC0-\xDF][\x80-\xBF]', '[\xE0-\xEF][\x80-\xBF]{2}', '[\xF0-\xF7][\x80-\xBF]{3}'].join('|'),'g'); var cb_btou = function(cccc) { switch (cccc.length) { case 4: var cp = ((0x07 & cccc.charCodeAt(0)) << 18) | ((0x3f & cccc.charCodeAt(1)) << 12) | ((0x3f & cccc.charCodeAt(2)) << 6) | (0x3f & cccc.charCodeAt(3)), offset = cp - 0x10000; return (fromCharCode((offset >>> 10) + 0xD800) + fromCharCode((offset & 0x3FF) + 0xDC00)); case 3: return fromCharCode(((0x0f & cccc.charCodeAt(0)) << 12) | ((0x3f & cccc.charCodeAt(1)) << 6) | (0x3f & cccc.charCodeAt(2))); default: return fromCharCode(((0x1f & cccc.charCodeAt(0)) << 6) | (0x3f & cccc.charCodeAt(1))); } }; var btou = function(b) { return b.replace(re_btou, cb_btou)
特别声明:本站部分内容收集于互联网是出于更直观传递信息的目的。该内容版权归原作者所有,并不代表本站赞同其观点和对其真实性负责。如该内容涉及任何第三方合法权利,请及时与824310991@qq.com联系,我们会及时反馈并处理完毕。