Use of Base64 and gzip in JavaScript

Transcoding and decoding of base64

/** * UTF16 and UTF8 conversion table * u+00000000–u+0000007f 0xxxxxxx* u+00000080–u+000007ff 110xxxxx 10xxxxxx* u+00000800–u+00 00FFFF 1110xxxx 10xxxxxx 10xxxxxx* u+00010000–u+001fffff 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx* u+00200000–u+03fffff F 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx* u+04000000–u+7fffffff 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 1 0xxxxxx*/varBase64 = {    //transcoding Tablestable: [' A ', ' B ', ' C ', ' D ', ' E ', ' F ', ' G ', ' H ',            ' I ', ' J ', ' K ', ' L ', ' M ', ' N ', ' O ', ' P ',            ' Q ', ' R ', ' S ', ' T ', ' U ', ' V ', ' W ', ' X ',            ' Y ', ' Z ', ' A ', ' B ', ' C ', ' d ', ' e ', ' F ',            ' G ', ' h ', ' I ', ' j ', ' K ', ' l ', ' m ', ' n ',            ' O ', ' P ', ' Q ', ' R ', ' s ', ' t ', ' u ', ' V ',            ' W ', ' x ', ' y ', ' z ', ' 0 ', ' 1 ', ' 2 ', ' 3 ',            ' 4 ', ' 5 ', ' 6 ', ' 7 ', ' 8 ', ' 9 ', ' + ', '/',        =], Utf16toutf8:function(str) {varres = [], Len =str.length;  for(vari = 0; i < Len; i++) {            varCode =str.charcodeat (i); if(Code > 0x0000 && Code <= 0x007F) {                //single Byte, here is not considered 0x0000, because it is empty byte                //u+00000000–u+0000007f 0xxxxxxxRes.push (Str.charat (i)); } Else if(Code >= 0x0080 && code <= 0x07ff) {                //Double byte                //u+00000080–u+000007ff 110xxxxx 10xxxxxx                //110xxxxx                varByte1 = 0xC0 | (Code >> 6) & 0x1F); //10xxxxxx                varByte2 = 0x80 | (Code & 0x3F);            Res.push (String.fromCharCode (byte1), String.fromCharCode (Byte2)); } Else if(Code >= 0x0800 && code <= 0xFFFF) {                //three bytes                //u+00000800–u+0000ffff 1110xxxx 10xxxxxx 10xxxxxx                //1110xxxx                varByte1 = 0xE0 | (Code >>) & 0x0F); //10xxxxxx                varByte2 = 0x80 | (Code >> 6) & 0x3F); //10xxxxxx                varByte3 = 0x80 | (Code & 0x3F);                     Res.push (String.fromCharCode (byte1), String.fromCharCode (Byte2),            String.fromCharCode (Byte3)); } Else if(Code >= 0x00010000 && code <= 0X001FFFFF) {                //Four bytes                //u+00010000–u+001fffff 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx}Else if(Code >= 0x00200000 && code <= 0X03FFFFFF) {                //Five bytes                //u+00200000–u+03ffffff 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx}Else /** IF (code >= 0x04000000 && Code <= 0x7FFFFFFF)*/ {                //Six bytes                //u+04000000–u+7fffffff 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx            }        }         returnRes.join (' '); }, Utf8toutf16:function(str) {varres = [], Len =str.length; vari = 0;  for(vari = 0; i < Len; i++) {            varCode =str.charcodeat (i); //make a judgment on the first byte            if((Code >> 7) & 0xFF) = = 0x0) {                //Single byte                //0xxxxxxxRes.push (Str.charat (i)); } Else if((Code >> 5) & 0xFF) = = 0x6) {                //Double byte                //110xxxxx 10xxxxxx                varCode2 = str.charcodeat (+ +i); varByte1 = (Code & 0x1F) << 6; varByte2 = Code2 & 0x3F; varUTF16 = Byte1 |Byte2;            Res.push (Sting.fromcharcode (UTF16)); } Else if((Code >> 4) & 0xFF) = = 0xE) {                //three bytes                //1110xxxx 10xxxxxx 10xxxxxx                varCode2 = str.charcodeat (+ +i); varCode3 = str.charcodeat (+ +i); varbyte1 = (Code << 4) | ((Code2 >> 2) & 0x0F); varByte2 = ((Code2 & 0x03) << 6) | (Code3 & 0x3F); varUTF16 = ((Byte1 & 0x00FF) << 8) |byte2 Res.push (String.fromCharCode (UTF16)); } Else if((Code >> 3) & 0xFF) = = 0x1E) {                //Four bytes                //11110xxx 10xxxxxx 10xxxxxx 10xxxxxx}Else if((Code >> 2) & 0xFF) = = 0x3e) {                //Five bytes                //111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx}Else /** IF ((Code >> 1) & 0xFF) = = 0x7E)*/ {                //Six bytes                //1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx            }        }         returnRes.join (' '); }, encode:function(str) {if(!str) {            return‘‘; }        varUTF8 = This. Utf16toutf8 (str);//turn into UTF8        vari = 0;//Traverse Index        varLen =utf8.length; varres = [];  while(I <Len) {            varC1 = Utf8.charcodeat (i++) & 0xFF; Res.push ( This. TABLE[C1 >> 2]); //need to fill 2 x =            if(i = =Len) {Res.push ( This. table[(C1 & 0x3) << 4]); Res.push (' = = ');  Break; }            varC2 = Utf8.charcodeat (i++); //need to fill 1 x =            if(i = =Len) {Res.push ( This. table[((C1 & 0x3) << 4) | ((C2 >> 4) & 0x0F)]); Res.push ( This. table[(C2 & 0x0F) << 2]); Res.push (=);  Break; }            varC3 = Utf8.charcodeat (i++); Res.push ( This. table[((C1 & 0x3) << 4) | ((C2 >> 4) & 0x0F)]); Res.push ( This. table[((C2 & 0x0F) << 2) | ((C3 & 0xC0) >> 6)]); Res.push ( This. TABLE[C3 & 0x3F]); }         returnRes.join (' '); }, Decode:function(str) {if(!str) {            return‘‘; }         varLen =str.length; vari = 0; varres = [];  while(I <Len) {Code1= This. Table.indexof (Str.charat (i++)); Code2= This. Table.indexof (Str.charat (i++)); Code3= This. Table.indexof (Str.charat (i++)); Code4= This. Table.indexof (Str.charat (i++)); C1= (code1 << 2) | (Code2 >> 4); C2= ((Code2 & 0xF) << 4) | (Code3 >> 2); C3= ((Code3 & 0x3) << 6) |Code4;             Res.push (String.fromCharCode (C1)); if(Code3! = 64) {Res.push (String.fromCharCode (C2)); }            if(Code4! = 64) {Res.push (String.fromCharCode (C3)); }         }         return  This. Utf8toutf16 (Res.join (")); }, Decodetobytes:function(str) {if(!str) {            return‘‘; }         varLen =str.length; vari = 0; varres = [];  while(I <Len) {Code1= This. Table.indexof (Str.charat (i++)); Code2= This. Table.indexof (Str.charat (i++)); Code3= This. Table.indexof (Str.charat (i++)); Code4= This. Table.indexof (Str.charat (i++)); C1= (code1 << 2) | (Code2 >> 4); C2= ((Code2 & 0xF) << 4) | (Code3 >> 2); C3= ((Code3 & 0x3) << 6) |Code4;            Res.push (C1); if(Code2! = 64) {Res.push (C2); }            if(Code3! = 64) {Res.push (C3);         }} res.pop (); returnRes; }}; 

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Gzip transcoding and decoding (Zlib.js library)

Https://github.com/imaya/zlib.js/blob/master/README.en.md

Comes with an Encoding conversion library (text-encoding)

Https://github.com/inexorabletash/text-encoding

Use of Base64 and gzip in JavaScript