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Making selective changes to XML file



  • Hi,

    I am currently having a task of making that requires making selective changes to some XML.

    Lets say that the XML contains multiple elements with different tags A,B and C. I suppose to only make changes on the XML with tag B. There may be a modification / deletion / addition of the tag objects.

    In other words

    <A id ="pqr"/>
    <B id="a"/>
    <B id="1"/>
    <B id="2"/>
    <B id="3"/>
    

    can become something like:

    <A id ="pqr"/>
    <B id="3"/>
    <B id="jprs" name="somehtingOptional"/>
    

    I don't have much control over the reader (its an old code and changing it means missing all my deadlines). We now want to selectively make changes for tag B w/o affecting everything else.
    I tried using QXMLStreamWriter for this, but my implementation was basically truncate and re-write everything. Since I have no idea how tag A and C can be written (really old code and no one in the surviving team has any idea).
    I have another implementation where I am basically duplicating the data which isn't tag B and just dump it into the file later. I don't like wasting space that way.
    I tried using QDomDocument for doing this, but my setContent keeps returning false for some reason.

    I am wondering if someone can suggest me something for this. I really don't want to duplicate data (double reading, memory wastage etc.).

    Thanks


  • Lifetime Qt Champion

    Hi and welcome to devnet,

    You can find the reason using the three last parameters of the setContent method.


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