【极简壁纸 - 技术分享】适用Vue的base64加密解密

极简壁纸2.0 地址: https://bz.zzzmh.cn 目前进度已开发到95%
近期有时间就会分享一下，我在开发过程中用到的一些小技术的简单用法和demo

前言

前端调用后端api过程中，某些用户输入的特殊情况下回出现乱码，这种情况下需要用到base64编码和解码来调用api传输数据。
百度上一个流传较广的base64.js的源码如下:

// base64.js 文件内容
function Base64() {  
    // private property  
    _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";  
    // public method for encoding  
    this.encode = function (input) {  
        var output = "";  
        var chr1, chr2, chr3, enc1, enc2, enc3, enc4;  
        var i = 0;  
        input = _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 +  
            _keyStr.charAt(enc1) + _keyStr.charAt(enc2) +  
            _keyStr.charAt(enc3) + _keyStr.charAt(enc4);  
        }  
        return output;  
    }  
    // public method for decoding  
    this.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 = _keyStr.indexOf(input.charAt(i++));  
            enc2 = _keyStr.indexOf(input.charAt(i++));  
            enc3 = _keyStr.indexOf(input.charAt(i++));  
            enc4 = _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 = _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 = c1 = c2 = 0;  
        while ( i < utftext.length ) {  
            c = utftext.charCodeAt(i);  
            if (c < 128) {  
                string += String.fromCharCode(c);  
                i++;  
            } else if((c > 191) && (c < 224)) {  
                c2 = utftext.charCodeAt(i+1);  
                string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));  
                i += 2;  
            } else {  
                c2 = utftext.charCodeAt(i+1);  
                c3 = utftext.charCodeAt(i+2);  
                string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));  
                i += 3;  
            }  
        }  
        return string;  
    }  
}

// 基本用法入下
//先实例化
var base = new Base64();
// 加密
var xxx = base.encode(xxx);
// 解密
var xxx = base.decode(xxx);

正文

1. 那么一般用法是引入前文这个js依赖，然后调用加密解密方法就可以了。但强迫症表示，为了这点代码，多引一次依赖，我能疯掉。。。
2. 就算直接把这段代码(es5语法)和vue的代码(es6语法)放在一起又很不统一，强迫症一样要疯掉。

于是我把这段代码简单粗暴的翻成了es6语法，直接能丢进vue的methods里使用。不多介绍了，最终代码如下：

encode: function (input) {
    let _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
    let chr1, chr2, chr3, enc1, enc2, enc3, enc4, i = 0, output = '', utftext = '';
    input = input.replace(/\r\n/g, "\n");
    for (let n = 0; n < input.length; n++) {
        let c = input.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);
        }

    }
    while (i < utftext.length) {
        chr1 = utftext.charCodeAt(i++);
        chr2 = utftext.charCodeAt(i++);
        chr3 = utftext.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 +
            _keyStr.charAt(enc1) + _keyStr.charAt(enc2) +
            _keyStr.charAt(enc3) + _keyStr.charAt(enc4);
    }
    return output;
},
decode: function (input) {
    let _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
    let chr1, chr2, chr3, enc1, enc2, enc3, enc4, i = 0, output = '';
    input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
    while (i < input.length) {
        enc1 = _keyStr.indexOf(input.charAt(i++));
        enc2 = _keyStr.indexOf(input.charAt(i++));
        enc3 = _keyStr.indexOf(input.charAt(i++));
        enc4 = _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);
        }
    }
    let string = '', c = 0, c1 = 0, c2 = 0, c3 = 0;
    i = 0;
    while (i < output.length) {
        c = output.charCodeAt(i);
        if (c < 128) {
            string += String.fromCharCode(c);
            i++;
        } else if ((c > 191) && (c < 224)) {
            c2 = output.charCodeAt(i + 1);
            string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
            i += 2;
        } else {
            c2 = output.charCodeAt(i + 1);
            c3 = output.charCodeAt(i + 2);
            string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
            i += 3;
        }
    }
    return string;
}

END

目前就是这些，之后还会分享一些开发极简壁纸时学到的技术。
也欢迎访问极简壁纸2.0 地址: https://bz.zzzmh.cn