src_xml_dom_qdom.cpp

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// Copyright (C) 2016 The Qt Company Ltd.

// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause

#include <iostream>

#include <cstring>

#include <QFile>

#include <QDomDocument>

#include <QDomImplementation>

void NodeElements();

void DomText();

void FirstElement();

void FileContent();

void DocAppend();

void XML_snippet_main();

using namespace std;

//! [0]

void XML_snippet_main()

QDomDocument doc;

QDomImplementation impl;

// This will create the element, but the resulting XML document will

// be invalid, because '~' is not a valid character in a tag name.

impl.setInvalidDataPolicy(QDomImplementation::AcceptInvalidChars);

QDomElement elt1 = doc.createElement("foo~bar");

// This will create an element with the tag name "foobar".

impl.setInvalidDataPolicy(QDomImplementation::DropInvalidChars);

QDomElement elt2 = doc.createElement("foo~bar");

// This will create a null element.

impl.setInvalidDataPolicy(QDomImplementation::ReturnNullNode);

QDomElement elt3 = doc.createElement("foo~bar");

//! [0]

void NodeElements()

//! [1]

QDomDocument d;

QString someXML;

d.setContent(someXML);

QDomNode n = d.firstChild();

while (!n.isNull()) {

    if (n.isElement()) {

        QDomElement e = n.toElement();

        cout << "Element name: " << qPrintable(e.tagName()) << '\n';

        break;

    n = n.nextSibling();

//! [1]

//! [2]

QDomDocument document;

QDomElement element1 = document.documentElement();

QDomElement element2 = element1;

//! [2]

//! [3]

QDomElement element3 = document.createElement("MyElement");

QDomElement element4 = document.createElement("MyElement");

//! [3]

//! [8]

QDomElement e;

//...

QDomAttr a = e.attributeNode("href");

cout << qPrintable(a.value()) << '\n';   // prints "http://qt-project.org"

a.setValue("http://qt-project.org/doc"); // change the node's attribute

QDomAttr a2 = e.attributeNode("href");

cout << qPrintable(a2.value()) << '\n';  // prints "http://qt-project.org/doc"

//! [8]

void DomText()

QDomDocument doc;

//! [10]

QString text;

QDomElement element = doc.documentElement();

for(QDomNode n = element.firstChild(); !n.isNull(); n = n.nextSibling())

    QDomText t = n.toText();

    if (!t.isNull())

        text += t.data();

//! [10]

void FileContent()

//! [16]

QDomDocument doc("mydocument");

QFile file("mydocument.xml");

if (!file.open(QIODevice::ReadOnly))

    return;

if (!doc.setContent(&file)) {

    file.close();

    return;

file.close();

// print out the element names of all elements that are direct children

// of the outermost element.

QDomElement docElem = doc.documentElement();

QDomNode n = docElem.firstChild();

while(!n.isNull()) {

    QDomElement e = n.toElement(); // try to convert the node to an element.

    if(!e.isNull()) {

        cout << qPrintable(e.tagName()) << '\n'; // the node really is an element.

    n = n.nextSibling();

// Here we append a new element to the end of the document

QDomElement elem = doc.createElement("img");

elem.setAttribute("src", "myimage.png");

docElem.appendChild(elem);

//! [16]

void DocAppend()

//! [17]

QDomDocument doc;

QDomElement root = doc.createElement("MyML");

doc.appendChild(root);

QDomElement tag = doc.createElement("Greeting");

root.appendChild(tag);

QDomText t = doc.createTextNode("Hello World");

tag.appendChild(t);

QString xml = doc.toString();

//! [17]