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Special characters in attributes


I am reading/writing XML using DOM from C++.  Some attributes are a C-like expression that can include &, <, > as well as single- and/or double-quotes.

I have found lots of info on XML attributes that basically says if you want to use a double-quote enclose the attribute in single-quotes and vice-versa.  None address the issue of including both double- and single-quotes in the same attribute text.

Also, I assume that I have to converts and ampersand (&) to &amp; when writing the XML, and convert back when reading.  Putting an & in the attribute text does not work, although I have never read that it should be a problem.
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Independent Consultant
Commented:
aphillips,

Basically any reserved character according to the XML spec. has to be escaped (or quoted) with the &...; sequence you mentioned.

See 2.4 of the spec for details:

http://www.w3.org/TR/2000/REC-xml-20001006#syntax

& becomes &amp;
' becomes &apos;
" becomes &quot;

etc..

If you're using the DOM, the conversions should be transparent -- you shouldn't have to escape text strings manually.

Regards,
WMB

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Commented:
wbradney said:
> & becomes &amp;
> ' becomes &apos;
> " becomes &quot;
Thanks, I have never seen &apos; or &quot; before.  I also didn't know you could use &amp; in an attribute string.

> If you're using the DOM, the conversions should be transparent ...

You are right.  I was creating the XML by hand for testing.  The & was giving errors when reading the attributes but using DOM to create the XML this all becomes transparent.  

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