diff base64.js @ 0:96898e3812a5

initial push
author Sonny Piers <sonny.piers@gmail.com>
date Sun, 18 Dec 2011 19:03:28 +0100
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+++ b/base64.js
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+// This code was written by Tyler Akins and has been placed in the
+// public domain.  It would be nice if you left this header intact.
+// Base64 code from Tyler Akins -- http://rumkin.com
+
+var Base64 = (function () {
+    var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
+
+    var obj = {
+        /**
+         * Encodes a string in base64
+         * @param {String} input The string to encode in base64.
+         */
+        encode: function (input) {
+            var output = "";
+            var chr1, chr2, chr3;
+            var enc1, enc2, enc3, enc4;
+            var i = 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 & 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);
+            } while (i < input.length);
+
+            return output;
+        },
+
+        /**
+         * Decodes a base64 string.
+         * @param {String} input The string to decode.
+         */
+        decode: function (input) {
+            var output = "";
+            var chr1, chr2, chr3;
+            var enc1, enc2, enc3, enc4;
+            var i = 0;
+
+            // remove all characters that are not A-Z, a-z, 0-9, +, /, or =
+            input = input.replace(/[^A-Za-z0-9\+\/\=]/g, "");
+
+            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 & 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);
+                }
+            } while (i < input.length);
+
+            return output;
+        }
+    };
+
+    return obj;
+})();