How to encode a string in base64 in JScript [duplicate] - windows

Question

I am trying to use atob for converting base64 encoded data to string. I found its working fine in Mozilla and Chrome, but it is not working in IE. Please tell me any substitue for this, or how to make this work in IE

Answer 1

Go to this link and include js present there:
http://code.google.com/p/stringencoders/source/browse/trunk/javascript/base64.js?r=230
/*
* Copyright (c) 2010 Nick Galbreath
* See full license on http://code.google.com/p/stringencoders/source/browse/#svn/trunk/javascript
*/
var base64 = {};
base64.PADCHAR = '=';
base64.ALPHA = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
base64.makeDOMException = function() {
// sadly in FF,Safari,Chrome you can't make a DOMException
var e, tmp;
try {
return new DOMException(DOMException.INVALID_CHARACTER_ERR);
} catch (tmp) {
// not available, just passback a duck-typed equiv
// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/Error
// https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Global_Objects/Error/prototype
var ex = new Error("DOM Exception 5");
// ex.number and ex.description is IE-specific.
ex.code = ex.number = 5;
ex.name = ex.description = "INVALID_CHARACTER_ERR";
// Safari/Chrome output format
ex.toString = function() { return 'Error: ' + ex.name + ': ' + ex.message; };
return ex;
}
}
base64.getbyte64 = function(s,i) {
// This is oddly fast, except on Chrome/V8.
// Minimal or no improvement in performance by using a
// object with properties mapping chars to value (eg. 'A': 0)
var idx = base64.ALPHA.indexOf(s.charAt(i));
if (idx === -1) {
throw base64.makeDOMException();
}
return idx;
}
base64.decode = function(s) {
// convert to string
s = '' + s;
var getbyte64 = base64.getbyte64;
var pads, i, b10;
var imax = s.length
if (imax === 0) {
return s;
}
if (imax % 4 !== 0) {
throw base64.makeDOMException();
}
pads = 0
if (s.charAt(imax - 1) === base64.PADCHAR) {
pads = 1;
if (s.charAt(imax - 2) === base64.PADCHAR) {
pads = 2;
}
// either way, we want to ignore this last block
imax -= 4;
}
var x = [];
for (i = 0; i < imax; i += 4) {
b10 = (getbyte64(s,i) << 18) | (getbyte64(s,i+1) << 12) |
(getbyte64(s,i+2) << 6) | getbyte64(s,i+3);
x.push(String.fromCharCode(b10 >> 16, (b10 >> 8) & 0xff, b10 & 0xff));
}
switch (pads) {
case 1:
b10 = (getbyte64(s,i) << 18) | (getbyte64(s,i+1) << 12) | (getbyte64(s,i+2) << 6);
x.push(String.fromCharCode(b10 >> 16, (b10 >> 8) & 0xff));
break;
case 2:
b10 = (getbyte64(s,i) << 18) | (getbyte64(s,i+1) << 12);
x.push(String.fromCharCode(b10 >> 16));
break;
}
return x.join('');
}
base64.getbyte = function(s,i) {
var x = s.charCodeAt(i);
if (x > 255) {
throw base64.makeDOMException();
}
return x;
}
base64.encode = function(s) {
if (arguments.length !== 1) {
throw new SyntaxError("Not enough arguments");
}
var padchar = base64.PADCHAR;
var alpha = base64.ALPHA;
var getbyte = base64.getbyte;
var i, b10;
var x = [];
// convert to string
s = '' + s;
var imax = s.length - s.length % 3;
if (s.length === 0) {
return s;
}
for (i = 0; i < imax; i += 3) {
b10 = (getbyte(s,i) << 16) | (getbyte(s,i+1) << 8) | getbyte(s,i+2);
x.push(alpha.charAt(b10 >> 18));
x.push(alpha.charAt((b10 >> 12) & 0x3F));
x.push(alpha.charAt((b10 >> 6) & 0x3f));
x.push(alpha.charAt(b10 & 0x3f));
}
switch (s.length - imax) {
case 1:
b10 = getbyte(s,i) << 16;
x.push(alpha.charAt(b10 >> 18) + alpha.charAt((b10 >> 12) & 0x3F) +
padchar + padchar);
break;
case 2:
b10 = (getbyte(s,i) << 16) | (getbyte(s,i+1) << 8);
x.push(alpha.charAt(b10 >> 18) + alpha.charAt((b10 >> 12) & 0x3F) +
alpha.charAt((b10 >> 6) & 0x3f) + padchar);
break;
}
return x.join('');
}

Answer 2

atob and btoa are mozilla specific functions afterwards the support was extended to webkit browser like chrome,safari so it doesn't work in IE.
So better use some other functions like :-
/**
*
* Base64 encode / decode
* http://www.webtoolkit.info/
*
**/
var Base64 = {
// private property
_keyStr : "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
// public method for encoding
encode : function (input) {
var output = "";
var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
var i = 0;
input = Base64._utf8_encode(input);
while (i < input.length) {
chr1 = input.charCodeAt(i++);
chr2 = input.charCodeAt(i++);
chr3 = input.charCodeAt(i++);
enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;
if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output = output +
this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) +
this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);
}
return output;
},
// public method for decoding
decode : function (input) {
var output = "";
var chr1, chr2, chr3;
var enc1, enc2, enc3, enc4;
var i = 0;
input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
while (i < input.length) {
enc1 = this._keyStr.indexOf(input.charAt(i++));
enc2 = this._keyStr.indexOf(input.charAt(i++));
enc3 = this._keyStr.indexOf(input.charAt(i++));
enc4 = this._keyStr.indexOf(input.charAt(i++));
chr1 = (enc1 << 2) | (enc2 >> 4);
chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
chr3 = ((enc3 & 3) << 6) | enc4;
output = output + String.fromCharCode(chr1);
if (enc3 != 64) {
output = output + String.fromCharCode(chr2);
}
if (enc4 != 64) {
output = output + String.fromCharCode(chr3);
}
}
output = Base64._utf8_decode(output);
return output;
},
// private method for UTF-8 encoding
_utf8_encode : function (string) {
string = string.replace(/\r\n/g,"\n");
var utftext = "";
for (var n = 0; n < string.length; n++) {
var c = string.charCodeAt(n);
if (c < 128) {
utftext += String.fromCharCode(c);
}
else if((c > 127) && (c < 2048)) {
utftext += String.fromCharCode((c >> 6) | 192);
utftext += String.fromCharCode((c & 63) | 128);
}
else {
utftext += String.fromCharCode((c >> 12) | 224);
utftext += String.fromCharCode(((c >> 6) & 63) | 128);
utftext += String.fromCharCode((c & 63) | 128);
}
}
return utftext;
},
// private method for UTF-8 decoding
_utf8_decode : function (utftext) {
var string = "";
var i = 0;
var c = c1 = c2 = 0;
while ( i < utftext.length ) {
c = utftext.charCodeAt(i);
if (c < 128) {
string += String.fromCharCode(c);
i++;
}
else if((c > 191) && (c < 224)) {
c2 = utftext.charCodeAt(i+1);
string += String.fromCharCode(((c & 31) << 6) | (c2 & 63));
i += 2;
}
else {
c2 = utftext.charCodeAt(i+1);
c3 = utftext.charCodeAt(i+2);
string += String.fromCharCode(((c & 15) << 12) | ((c2 & 63) << 6) | (c3 & 63));
i += 3;
}
}
return string;
}
}
this will resolve your problem