Changes to Qt XML¶
Migrate Qt XML to Qt 6.
Qt 6 is a result of the conscious effort to make the framework more efficient and easy to use.
We try to maintain binary and source compatibility for all the public APIs in each release. But some changes were inevitable in an effort to make Qt a better framework.
In this topic we summarize those changes in Qt XML, and provide guidance to handle them.
Simple API for XML (SAX) parser¶
All SAX classes have been removed from Qt XML. Use
QXmlStreamReader for reading XML files. Here are some simple steps to port your current code to
For example, if you have code like
you can rewrite it as
QDom and QDomDocument¶
As SAX classes have been removed from Qt XML,
QDomDocument has been re-implemented using
QXmlStreamReader . This causes a few behavioral changes:
Attribute values will be normalized. For example,
<tag attr=" a \n b " />is equivalent to
<tag attr="a b"/>.
Identical qualified attribute names are no longer allowed. This means attributes of an element must have unique names.
Undeclared namespace prefixes are no longer allowed.
If you use
QDomDocument and rely on any of these, you must update your code and XML documents accordingly.
Qt Core5 compatibility library¶
If your application or library cannot be ported right now, the QXmlSimpleReader and related classes still exist in Qt5Compat to keep old code-bases working. If you want to use those SAX classes further, you need to link against the new Qt5Compat module and add this line to your qmake
QT += core5compat
In case you already ported your application or library to the cmake build system, add the following to your
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