How to escape the character entities in XML?

Question

I want to pass XML as a string in an XML attribute.

<activity evt="&lt;FHS&gt;
     &lt;act&gt;
         &lt;polyline penWidth=&quot;2&quot;  points=&quot;256,435 257,432 &quot;/&gt;
     &lt;/act&gt;
   &lt;/FHS&gt;" />

Here the "evt" attribute is the XML string, so escaping all the less-than, greater-than, etc characters by the appropriate character entities works fine.

The problem is I want a fragment to be interpreted as is - the character entities themselves should be treated as simple strings.

When the "evt" attribute is read and an XML is generated from it, it should look like

<FHS>
  <act>
    &lt;polyline penWidth=&quot;2&quot;  points=&quot;256,435 257,432 &quot;/&gt;
  </act>
</FHS>

Essentially, I want to escape the character entities. How is this possible?

Answer 1

So you need to escape the entities in the "inner" string twice. It would look like:

<polyline penWidth="2"  points="256,435 257,432 "/>

I must say I hope you have a good reason to do this :) The natural way of doing it would seem to be just nesting the elements, and extracting the child elements as needed.