Embedding inline HTML data in XML using the mx:XML tag with < and >

Question

What is best practice for embedding HTML within the
<mx:XML> tag? Programmatically, I can implement this
successfully:
[Bindable]
public var xmlDP:XML = <component data="&lt;" />;
However, I get the following error if I try to store the same
data inline in an mx:XML tag, as such:
<mx:XML id="xmlDP">
<component data="&lt;" />
</mx:XML>
Error #1095: XML parser failure: Unterminated attribute.
If I change the MXML tag as follows, it works fine:
<mx:XML id="xmlDP">
<component data="&amp;lt;" />
</mx:XML>
Unfortunately, I also can not source the mx:XML tag to an XML
file which uses &lt; or &gt; codes, as it yields the same
results. This leads me to believe that the <mx:XML> tag does
not support the special character codes for < and >, but why?
Incidentally, this code also gives a 1095 error:
<mx:XML id="xmlDP">
<component data="&#0060;" />
</mx:XML>
This is causing an issue with my source data as it is not
hand typed into Flex, and standard XML supports the &lt; and
&gt; codes. I have tried a full HTML string, as shown below,
but this also generates the error:
<mx:XML id="xmlDP">
<component data="&lt;b&gt;Test&lt;/b&gt;"
/>
</mx:XML>
Many thanks for any input you may have!

Answer 1

I’m generating the XML source file with
Microsoft’s XML Notepad 2007. It will encode invalid special
characters automatically. My understanding is that this is the
proper way to handle the less than symbol in a XML string, that is
to say using the &lt; code.
With respect to the escape and un-escape methods, I am able
to successfully implement these in AS, but not in MXML. This makes
sense considering they are AS methods, but I was hoping to be able
to do something like:
<mx:XML id="xmlDP">
<component data="escape('<');" />
</mx:XML>
This gives the following compilation error:
The value of attribute "data" must not contain the '<'
character.
As does using the escape character as such:
<mx:XML id="xmlDP">
<component data="\<" />
</mx:XML>
Below is an example of what the escape character may be used
for in AS:
var myString:String = "\"";
trace(myString);
// result: "
Likewise, I can escape the < character as such:
var myString:String = escape("<");
trace(myString);
// result: %3C
<mx:XML id="xmlDP">
<component data="%3C" />
</mx:XML>
trace(un-escape(xmlDP.@data));
// result: <
As you can see, using %3C and unescaping in AS will yield the
correct result; however, this is not a practical method of
representing the data in MXML as I would have to write an AS method
to un-escape the XML string anyway, so I might as well just store
the data in AS to begin with. I was hoping for a way to source an
mx:XML object, without having to load it into ActionScript
manually. Here’s an example of the functionality I would
expect:
<mx:XML id="xmlDP">
<component data="&gt;" />
</mx:XML>
trace(xmlDP.@data);
// result: >
Only this does not work for the less than symbol. I’m
assuming at this point that this is a bug in the Flex compiler.
Thanks again for your help troubleshooting this one!