我正在尝试导入在 Flash 中经过 Base64 编码的 XML 文件。导入相当简单：
var myXML:XML;
var myLoader:URLLoader = new URLLoader();
myLoader.load(new URLRequest("encoded.xml"));
myLoader.addEventListener(Event.COMPLETE, processXML);
function processXML(e:Event):void
{
myXML = new XML(e.target.data);
trace(myXML);
}
现在我想知道我如何解码它。我找到了一个我认为可以工作的类，但我不确定一旦导入它后如何将它应用到 XML。我的问题是我将如何使用下面的类来解码 XML，或者我应该采取另一种方法吗？
package com.base64 {
/**
* Encodes and decodes a base64 string.
* @authors Sven Dens - http://www.svendens.be
* @version 0.1
*
* Original Javascript implementation:
* Aardwulf Systems, www.aardwulf.com
* See: http://www.aardwulf.com/tutor/base64/base64.html
*/
import flash.system.System;
public class Base64 {
/**
* Variables
* @exclude
*/
protected static var base64chars:String = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
/**
* Encodes a base64 string.
*/
public static function encode(src:String):String {
var i:Number = 0;
var output:String = new String("");
var chr1:Number, chr2:Number, chr3:Number;
var enc1:Number, enc2:Number, enc3:Number, enc4:Number;
while (i < src.length) {
chr1 = src.charCodeAt(i++);
chr2 = src.charCodeAt(i++);
chr3 = src.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 += base64chars.charAt(enc1)+base64chars.charAt(enc2);
output += base64chars.charAt(enc3)+base64chars.charAt(enc4)
}
return output;
}
/**
* Decodes a base64 string.
*/
public static function decode(src:String):String {
var i:Number = 0;
var output:String = new String("");
var chr1:Number, chr2:Number, chr3:Number;
var enc1:Number, enc2:Number, enc3:Number, enc4:Number;
while (i < src.length) {
enc1 = base64chars.indexOf(src.charAt(i++));
enc2 = base64chars.indexOf(src.charAt(i++));
enc3 = base64chars.indexOf(src.charAt(i++));
enc4 = base64chars.indexOf(src.charAt(i++));
chr1 = (enc1 << 2) | (enc2 >> 4);
chr2 = ((enc2 & 15) << 4) | (enc3 >> 2);
chr3 = ((enc3 & 3) << 6) | enc4;
output += String.fromCharCode(chr1);
if (enc3 != 64) output = output+String.fromCharCode(chr2);
if (enc4 != 64) output = output+String.fromCharCode(chr3);
}
return output;
}
}
}