JAVA高级面试进阶训练营视频教程

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<script src="../static/js/jquery.base64.js"></script>

<script src="../webstatic/js/jquery.min.js"></script>
首先需要明白一点的是：
js前端默认采用utf-16方式编码；
后台数据加密前将数据转成了utf-8格式；
因此解密后需要进行格式转换，从utf-8转为utf-16。

utf8转为utf16：
var utf8to16 = function(str) {
                var out, i, len, c;
                var char2, char3;
                out = "";
                len = str.length;
                i = 0;
                while(i < len) {
                    c = str.charCodeAt(i++);
                    switch(c >> 4)
                    {
                        case 0: case 1: case 2: case 3: case 4: case 5: case 6:case7:
                        // 0xxxxxxx
                        out += str.charAt(i-1);
                        break;
                        case 12: case 13:
                        // 110x xxxx 10xx xxxx
                        char2 = str.charCodeAt(i++);
                        out += String.fromCharCode(((c & 0x1F) << 6) | (char2&0x3F));
                        break;
                        case 14:
                        // 1110 xxxx 10xx xxxx 10xx xxxx
                            char2 = str.charCodeAt(i++);
                            char3 = str.charCodeAt(i++);
                            out += String.fromCharCode(((c & 0x0F) << 12) |
                                ((char2 & 0x3F) << 6) |
                                ((char3 & 0x3F) << 0));
                            break;
                    }
                }
                return out;
            }

utf16转为utf8：
var utf16to8 = function(str) {
                var out, i, len, c;
                out = "";
                len = str.length;
                for(i = 0; i < len; i++) {
                    c = str.charCodeAt(i);
                    if ((c >= 0x0001) && (c <= 0x007F)) {
                        out += str.charAt(i);
                    } else if (c > 0x07FF) {
                        out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
                        out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
                        out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
                    } else {
                        out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
                        out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
                    }
                }
                return out;
            }



内容也是摘自博友，仅供学习参考。