Implementation of JavaScript BASE64 algorithm

JS version Base 64 algorithm Base64.js

varKeystr = "Abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789+/=";//BASE64 encoding an ANSI-encoded stringfunctionencode64 (input) {varOutput = "";varCHR1, CHR2, CHR3 = "";varENC1, Enc2, enc3, Enc4 = "";vari = 0; Do{chr1= Input.charcodeat (i++); CHR2= Input.charcodeat (i++); Chr3= Input.charcodeat (i++); Enc1= Chr1 >> 2; Enc2= ((Chr1 & 3) << 4) | (CHR2 >> 4); Enc3= ((CHR2 &) << 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); Chr1= CHR2 = CHR3 = ""; Enc1= ENC2 = Enc3 = Enc4 = "";}  while(I <input.length);returnoutput;}//converting an BASE64 encoded string to an ANSI-encoded stringfunctiondecode64 (input) {varOutput = "";varCHR1, CHR2, CHR3 = "";varENC1, Enc2, enc3, Enc4 = "";vari = 0; if(input.length% 4! = 0) {return"";}varBase64test =/[^a-za-z0-9\+\/\=]/G;if(base64test.exec (input)) {return"";} Do{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 &) << 4) | (Enc3 >> 2); Chr3= ((enc3 & 3) << 6) |Enc4; Output= output +String.fromCharCode (CHR1);if(Enc3! = 64) {Output+=String.fromCharCode (CHR2);}if(Enc4! = 64) {Output+=String.fromCharCode (CHR3);} CHR1= CHR2 = CHR3 = ""; Enc1= ENC2 = Enc3 = Enc4 = "";}  while(I <input.length);returnoutput;} functionUtf16to8 (str) {varOut , 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 >> b) & 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)); }  }  returnOut ;} functionutf8to16 (str) {varOut , I, Len, C; varChar2, Char3; out= ""; Len=str.length; I= 0;  while(I <Len) {C= Str.charcodeat (i++); Switch(C >> 4) {       Case0: Case1: Case2: Case3: Case4: Case5: Case6: Case7:        //0xxxxxxxOut + = Str.charat (i-1);  Break;  Case12: Case13:        //110x xxxx 10xx xxxxCHAR2 = Str.charcodeat (i++); out+ = String.fromCharCode (((C & 0x1F) << 6) | (Char2 & 0x3F));  Break;  Case14:        //1110 xxxx 10xx xxxx 10xx xxxxCHAR2 = Str.charcodeat (i++); Char3= Str.charcodeat (i++); out+ = String.fromCharCode (((C & 0x0F) << 12) |((Char2& 0x3F) << 6) |((Char3& 0x3F) << 0));  Break; }  }  returnOut ;}

Examples of parsing in JS:

Encryption

var testcode= "test88"; var resultcode= encode64 (Utf16to8 (Testcode)); Console.log (ResultCode);

Output

DGVzdDg4

Decrypt

var testcode= "DGVzdDg4"; ResultCode= utf8to16 (decode64 (Testcode)); Console.log (ResultCode );

Output

Test88

Implementation of JavaScript BASE64 algorithm