js base64加密与C#后台base64解密

js代码

  1   function encode64(input) {
  2         var output = "";
  3         var base = new Base64();
  4         var output = base.encode(input);
  5         return output;
  6     }
  7 
  8     function Base64() {
  9 
 10         // private property
 11         _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
 12 
 13         // public method for encoding
 14         this.encode = function (input) {
 15             var output = "";
 16             var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
 17             var i = 0;
 18             input = _utf8_encode(input);
 19             while (i < input.length) {
 20                 chr1 = input.charCodeAt(i++);
 21                 chr2 = input.charCodeAt(i++);
 22                 chr3 = input.charCodeAt(i++);
 23                 enc1 = chr1 >> 2;
 24                 enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
 25                 enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
 26                 enc4 = chr3 & 63;
 27                 if (isNaN(chr2)) {
 28                     enc3 = enc4 = 64;
 29                 } else if (isNaN(chr3)) {
 30                     enc4 = 64;
 31                 }
 32                 output = output +
 33                 _keyStr.charAt(enc1) + _keyStr.charAt(enc2) +
 34                 _keyStr.charAt(enc3) + _keyStr.charAt(enc4);
 35             }
 36             return output;
 37         }
 38 
 39         // public method for decoding
 40         this.decode = function (input) {
 41             var output = "";
 42             var chr1, chr2, chr3;
 43             var enc1, enc2, enc3, enc4;
 44             var i = 0;
 45             input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
 46             while (i < input.length) {
 47                 enc1 = _keyStr.indexOf(input.charAt(i++));
 48                 enc2 = _keyStr.indexOf(input.charAt(i++));
 49                 enc3 = _keyStr.indexOf(input.charAt(i++));
 50                 enc4 = _keyStr.indexOf(input.charAt(i++));
 51                 chr1 = (enc1 << 2) | (enc2 >> 4);
 52                 chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
 53                 chr3 = ((enc3 & 3) << 6) | enc4;
 54                 output = output + String.fromCharCode(chr1);
 55                 if (enc3 != 64) {
 56                     output = output + String.fromCharCode(chr2);
 57                 }
 58                 if (enc4 != 64) {
 59                     output = output + String.fromCharCode(chr3);
 60                 }
 61             }
 62             output = _utf8_decode(output);
 63             return output;
 64         }
 65 
 66         // private method for UTF-8 encoding
 67         _utf8_encode = function (string) {
 68             string = string.replace(/\r\n/g, "\n");
 69             var utftext = "";
 70             for (var n = 0; n < string.length; n++) {
 71                 var c = string.charCodeAt(n);
 72                 if (c < 128) {
 73                     utftext += String.fromCharCode(c);
 74                 } else if ((c > 127) && (c < 2048)) {
 75                     utftext += String.fromCharCode((c >> 6) | 192);
 76                     utftext += String.fromCharCode((c & 63) | 128);
 77                 } else {
 78                     utftext += String.fromCharCode((c >> 12) | 224);
 79                     utftext += String.fromCharCode(((c >> 6) & 63) | 128);
 80                     utftext += String.fromCharCode((c & 63) | 128);
 81                 }
 82 
 83             }
 84             return utftext;
 85         }
 86 
 87         // private method for UTF-8 decoding
 88         _utf8_decode = function (utftext) {
 89             var string = "";
 90             var i = 0;
 91             var c = c1 = c2 = 0;
 92             while (i < utftext.length) {
 93                 c = utftext.charCodeAt(i);
 94                 if (c < 128) {
 95                     string += String.fromCharCode(c);
 96                     i++;
 97                 } else if ((c > 191) && (c < 224)) {
 98                     c2 = utftext.charCodeAt(i + 1);
 99                     string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
100                     i += 2;
101                 } else {
102                     c2 = utftext.charCodeAt(i + 1);
103                     c3 = utftext.charCodeAt(i + 2);
104                     string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
105                     i += 3;
106                 }
107             }
108             return string;
109         }
110     }

View Code

C#后台代码

   /// <summary>
        /// base64解密
        /// </summary>
        /// <param name="encode">编码，与js一致</param>
        /// <param name="result">加密源字符串</param>
        /// <returns></returns>
        public static string DecodeBase64(Encoding encode, string result)
        {
            string decode = "";
            byte[] bytes = Convert.FromBase64String(result);
            try
            {
                decode = encode.GetString(bytes);
            }
            catch
            {
                decode = result;
            }
            return decode;
        }