Created
December 6, 2012 04:03
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Convert utf8 to utf16 and reverse
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var base64 = {}; | |
(function(exports) { | |
var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; | |
var base64DecodeChars = new Array(-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, -1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1); | |
function base64encode(str) { | |
var out, i, len; | |
var c1, c2, c3; | |
len = str.length; | |
i = 0; | |
out = ""; | |
while (i < len) { | |
c1 = str.charCodeAt(i++) & 0xff; | |
if (i == len) { | |
out += base64EncodeChars.charAt(c1 >> 2); | |
out += base64EncodeChars.charAt((c1 & 0x3) << 4); | |
out += "=="; | |
break; | |
} | |
c2 = str.charCodeAt(i++); | |
if (i == len) { | |
out += base64EncodeChars.charAt(c1 >> 2); | |
out += base64EncodeChars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4)); | |
out += base64EncodeChars.charAt((c2 & 0xF) << 2); | |
out += "="; | |
break; | |
} | |
c3 = str.charCodeAt(i++); | |
out += base64EncodeChars.charAt(c1 >> 2); | |
out += base64EncodeChars.charAt(((c1 & 0x3) << 4) | ((c2 & 0xF0) >> 4)); | |
out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >> 6)); | |
out += base64EncodeChars.charAt(c3 & 0x3F); | |
} | |
return out; | |
} | |
function base64decode(str) { | |
var c1, c2, c3, c4; | |
var i, len, out; | |
len = str.length; | |
i = 0; | |
out = ""; | |
while (i < len) { | |
/* c1 */ | |
do { | |
c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff]; | |
} while ( i < len && c1 == - 1 ); | |
if (c1 == -1) | |
break; | |
/* c2 */ | |
do { | |
c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff]; | |
} while ( i < len && c2 == - 1 ); | |
if (c2 == -1) | |
break; | |
out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4)); | |
/* c3 */ | |
do { | |
c3 = str.charCodeAt(i++) & 0xff; | |
if (c3 == 61) | |
return out; | |
c3 = base64DecodeChars[c3]; | |
} while ( i < len && c3 == - 1 ); | |
if (c3 == -1) | |
break; | |
out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2)); | |
/* c4 */ | |
do { | |
c4 = str.charCodeAt(i++) & 0xff; | |
if (c4 == 61) | |
return out; | |
c4 = base64DecodeChars[c4]; | |
} while ( i < len && c4 == - 1 ); | |
if (c4 == -1) | |
break; | |
out += String.fromCharCode(((c3 & 0x03) << 6) | c4); | |
} | |
return out; | |
} | |
function utf16to8(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; | |
} | |
function utf8to16(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: | |
case 7: | |
// 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 xxxx10xx xxxx10xx xxxx | |
char2 = str.charCodeAt(i++); | |
char3 = str.charCodeAt(i++); | |
out += String.fromCharCode(((c & 0x0F) << 12) | ((char2 & 0x3F) << 6) | ((char3 & 0x3F) << 0)); | |
break; | |
} | |
} | |
return out; | |
} | |
exports.base64encode = function(str) { | |
return base64encode(str); | |
}; | |
exports.base64decode = function(str) { | |
return base64decode(str); | |
}; | |
})(base64); |
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