base64.js

/**
 *  Base64 encode / decode
 *  Based on http://www.webtoolkit.info/javascript-base64.html
 **/
Base64 = function() {
	// private property
	var _keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
	return {
		encode : function (input) {
			var output = "";
			var chr1, chr2, chr3, enc1, enc2, enc3, enc4;
			var i = 0;

			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 +
				_keyStr.charAt(enc1) + _keyStr.charAt(enc2) +
				_keyStr.charAt(enc3) + _keyStr.charAt(enc4);
			}
			return output;
		},
		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 = _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 & 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);
				}
			}
			return output;
		}
	};
	alert('defined');
}();