1/** 2* 3* Base64 encode / decode 4* http://www.webtoolkit.info/ 5* 6**/ 7 8var Base64 = { 9 10 // private property 11 _keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=", 12 13 // public method for encoding 14 encode : function (input) { 15 var output = ""; 16 var chr1, chr2, chr3, enc1, enc2, enc3, enc4; 17 var i = 0; 18 19 input = Base64._utf8_encode(input); 20 21 while (i < input.length) { 22 23 chr1 = input.charCodeAt(i++); 24 chr2 = input.charCodeAt(i++); 25 chr3 = input.charCodeAt(i++); 26 27 enc1 = chr1 >> 2; 28 enc2 = ((chr1 & 3) << 4) | (chr2 >> 4); 29 enc3 = ((chr2 & 15) << 2) | (chr3 >> 6); 30 enc4 = chr3 & 63; 31 32 if (isNaN(chr2)) { 33 enc3 = enc4 = 64; 34 } else if (isNaN(chr3)) { 35 enc4 = 64; 36 } 37 38 output = output + 39 this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + 40 this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4); 41 42 } 43 44 return output; 45 }, 46 47 // public method for decoding 48 decode : function (input) { 49 var output = ""; 50 var chr1, chr2, chr3; 51 var enc1, enc2, enc3, enc4; 52 var i = 0; 53 54 input = input.replace(/[^A-Za-z0-9\+\/\=]/g, ""); 55 56 while (i < input.length) { 57 58 enc1 = this._keyStr.indexOf(input.charAt(i++)); 59 enc2 = this._keyStr.indexOf(input.charAt(i++)); 60 enc3 = this._keyStr.indexOf(input.charAt(i++)); 61 enc4 = this._keyStr.indexOf(input.charAt(i++)); 62 63 chr1 = (enc1 << 2) | (enc2 >> 4); 64 chr2 = ((enc2 & 15) << 4) | (enc3 >> 2); 65 chr3 = ((enc3 & 3) << 6) | enc4; 66 67 output = output + String.fromCharCode(chr1); 68 69 if (enc3 != 64) { 70 output = output + String.fromCharCode(chr2); 71 } 72 if (enc4 != 64) { 73 output = output + String.fromCharCode(chr3); 74 } 75 76 } 77 78 output = Base64._utf8_decode(output); 79 80 return output; 81 82 }, 83 84 // private method for UTF-8 encoding 85 _utf8_encode : function (string) { 86 string = string.replace(/\r\n/g,"\n"); 87 var utftext = ""; 88 89 for (var n = 0; n < string.length; n++) { 90 91 var c = string.charCodeAt(n); 92 93 if (c < 128) { 94 utftext += String.fromCharCode(c); 95 } 96 else if((c > 127) && (c < 2048)) { 97 utftext += String.fromCharCode((c >> 6) | 192); 98 utftext += String.fromCharCode((c & 63) | 128); 99 } 100 else { 101 utftext += String.fromCharCode((c >> 12) | 224); 102 utftext += String.fromCharCode(((c >> 6) & 63) | 128); 103 utftext += String.fromCharCode((c & 63) | 128); 104 } 105 106 } 107 108 return utftext; 109 }, 110 111 // private method for UTF-8 decoding 112 _utf8_decode : function (utftext) { 113 var string = ""; 114 var i = 0; 115 var c = c1 = c2 = 0; 116 117 while ( i < utftext.length ) { 118 119 c = utftext.charCodeAt(i); 120 121 if (c < 128) { 122 string += String.fromCharCode(c); 123 i++; 124 } 125 else if((c > 191) && (c < 224)) { 126 c2 = utftext.charCodeAt(i+1); 127 string += String.fromCharCode(((c & 31) << 6) | (c2 & 63)); 128 i += 2; 129 } 130 else { 131 c2 = utftext.charCodeAt(i+1); 132 c3 = utftext.charCodeAt(i+2); 133 string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63)); 134 i += 3; 135 } 136 137 } 138 139 return string; 140 } 141 142}