Hello, has anyone else noticed that AIR's XML.appendChild() implementation
differs in behaviour from the regular Flex/Flash Player? In particular,
AIR appears to perform XML escaping of strings, while Flex/FP sort of
expects already-escaped Strings?
The following example yields different results in AIR vs Flex:
<mx:Script>
<![CDATA[
protected function doit(e:Event):void
{
var x:XML = <outer />;
var y:XML = <inner />;
y.appendChild('hello <&> test');
x.appendChild(y);
txt1.text = x.toString();
txt2.text = x.toXMLString();
}
]]>
</mx:Script>
<mx:Button click='doit(event)' label='Click' />
<mx:TextArea id='txt1' width="100%" height="50%" >
</mx:TextArea>
<mx:TextArea id='txt2' width="100%" height="50%" >
</mx:TextArea>
Output in Flex:
<outer>
<inner>hello <&> test</inner>
</outer>
Output in AIR:
<outer>
<inner>hello &lt;&amp;&gt; test</inner>
</outer>
Note the double XML encoding in AIR.
The AIR behaviour is of course the most correct; one would
really expect "y.appendChild('hello <&> test');" to be proper API
usage, but that just breaks the flash player. So, to handle
arbitrary user input (including stuff that resembles XML markup)
to an XML node value in FP it is necessary to manually apply
XMl encoding to the string before passing it into appendChild(),
but in AIR this naturally results in doubly-encoded text nodes.
This is particularly problematic when working with flex library
projects that are shared between flex and air projects. Guess
I'll need to add some air detection code, and only do the
manual XML encoding on the string if running outside of AIR.
(Also, trying to use CDATA notes doesn't work either, especially
if the text to escape contains ]]>)
Comments?
