Read an XML content

Table of Contents

• Read an XML file
• Read an XML Stream
• Access at all Element datas
• All example file

The first thing to do when reading or writing a XML file/stream, is to declare the Document interface

Include exml

#include <exml/exml.hpp>

Declare document interface

    exml::Document doc;

Read an XML file

File to read: "read.xml"

<?xml version="1.0" encoding="UTF-8" standalone="true"?>
<!-- my comment -->
<exml attributeExample="my data attribute">
    coucou
    <!-- comment -->
    <subNodeA/>
    <subNodeB/>
</exml>

Reading a file is done like this:

    bool retParse = doc.load("DATA:read.xml");

The file naming is manage by etk::FSNode that provide "DATA:" start string for internal application asset. You can use external path like "./plop/file.xml" too.

Read an XML Stream

Reading a stream is done like this:

    std::string stream = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"true\"?>"
                         "<!-- my comment -->"
                         "<exml attributeExample=\"my data attribute\">coucou</exml>";
    bool retParse = doc.parse(stream);

In C and C++ it is very hard to read string with the \" then to simplify parsing of xml the parser engine support the use of simple ' interface:

    std::string stream = "<?xml version='1.0' encoding='UTF-8' standalone='true'?>"
                         "<!-- my comment -->"
                         "<exml attributeExample='my data attribute'>coucou</exml>";
    bool retParse = doc.parse(stream);

Access at all Element datas

In an exml::Element (or exml::Document) the sub-nodes are accessible threw an abstraction class stores in an element name nodes

Get a node with its name:

    exml::Element element = doc.nodes["exml"];

Reading all file nodes:

    for (const auto itElem: element.nodes) {
        if (itElem.isElement() == true) {
            // get the <XXXX ... name
            std::string value = itElem.toElement().getValue();
            TEST_INFO("         '" << value << "'");
        } else {
            // simple debug for other type:
            TEST_INFO("         ** " << itElem);
        }
    }

note: the itElem is a simple exml::Node that can be all the xml type. you can change the type by calling: toDocument(), toElement(), toString() ...

In a C style mode:

    for (size_t iii=0; iii<element.nodes.size(); ++iii) {
        const exml::Node node = element.nodes[iii];
        if (node.isElement() == true) {
            // get the <XXXX ... name
            std::string value = node.toElement().getValue();
            TEST_INFO("         '" << value << "'");
        } else {
            // simple debug for other type:
            TEST_INFO("         ** " << node);
        }
    }

In an exml::Element (or exml::Document or exml::Declaration) the sub-nodes are accessible threw an abstraction class stores in an element name attributes

Reading all Attributes of one node:

    for (const auto itElem: element.attributes) {
        std::string value = itElem.getValue();
        TEST_INFO("         '" << value << "'");
    }
    TEST_INFO("     list of attribute in C:");

In a C style mode:

    for (size_t iii=0; iii<element.attributes.size(); ++iii) {
        const exml::Attribute attr = element.attributes[iii];
        std::string value = attr.getValue();
        TEST_INFO("         '" << value << "'");
    }

Get an attribute data:

    std::string attributeValue = element.attributes["attributeExample"];
    TEST_INFO("     direct get: '" << attributeValue << "'");

In an exml::Element (or exml::Document) the internal data text can be accessible threw the interface:

Get all the data in an element in text mode:

    std::string internalData = element.getText();

All example file

#include <test-debug/debug.hpp>
#include <exml/exml.hpp>
#include "read.hpp"


static void readFromFile() {
    exml::Document doc;
    bool retParse = doc.load("DATA:read.xml");
    TEST_INFO("parse ret = " << retParse);
    TEST_INFO("Debug display of the tree:");
    doc.display();
}

static void readFromString1() {
    exml::Document doc;
    TEST_INFO("parse");
    std::string stream = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"true\"?>"
                         "<!-- my comment -->"
                         "<exml attributeExample=\"my data attribute\">coucou</exml>";
    bool retParse = doc.parse(stream);
    TEST_INFO("parse ret = " << retParse);
    TEST_INFO("Debug display of the tree:");
    doc.display();
}

static void readFromString2() {
    exml::Document doc;
    TEST_INFO("parse");
    std::string stream = "<?xml version='1.0' encoding='UTF-8' standalone='true'?>"
                         "<!-- my comment -->"
                         "<exml attributeExample='my data attribute'>coucou</exml>";
    bool retParse = doc.parse(stream);
    TEST_INFO("parse ret = " << retParse);
    TEST_INFO("Debug display of the tree:");
    doc.display();
}


static void readFull() {
    exml::Document doc;
    TEST_INFO("parse");
    bool retParse = doc.load("DATA:read.xml");
    TEST_INFO("parse ret = " << retParse);
    TEST_INFO("Debug display of the tree:");
    doc.display();
    TEST_INFO("list of attribute:");
    for (auto it: doc.attributes) {
        TEST_INFO(" " << it);
    }
    TEST_INFO("list of sub-node:");
    for (const auto it: doc.nodes) {
        TEST_INFO(" " << it);
        if (it.isElement() == false) {
            continue;
        }
        exml::Element elem = it.toElement();
        if (elem.exist() == false) {
            continue;
        }
        TEST_INFO("     list of attribute:");
        for (const auto itElem: elem.attributes) {
            TEST_INFO("         " << itElem);
        }
        TEST_INFO("     list of sub-node:");
        for (const auto itElem: elem.nodes) {
            TEST_INFO("         " << itElem);
        }
    }
    TEST_INFO(" Direct get node exml:");
    exml::Element element = doc.nodes["exml"];
    TEST_INFO("     list of attribute:");
    for (const auto itElem: element.attributes) {
        std::string value = itElem.getValue();
        TEST_INFO("         '" << value << "'");
    }
    TEST_INFO("     list of attribute in C:");
    for (size_t iii=0; iii<element.attributes.size(); ++iii) {
        const exml::Attribute attr = element.attributes[iii];
        std::string value = attr.getValue();
        TEST_INFO("         '" << value << "'");
    }
    std::string attributeValue = element.attributes["attributeExample"];
    TEST_INFO("     direct get: '" << attributeValue << "'");
    TEST_INFO("     list of sub-node:");
    for (const auto itElem: element.nodes) {
        if (itElem.isElement() == true) {
            // get the <XXXX ... name
            std::string value = itElem.toElement().getValue();
            TEST_INFO("         '" << value << "'");
        } else {
            // simple debug for other type:
            TEST_INFO("         ** " << itElem);
        }
    }
    TEST_INFO("     list of sub-node in C:");
    for (size_t iii=0; iii<element.nodes.size(); ++iii) {
        const exml::Node node = element.nodes[iii];
        if (node.isElement() == true) {
            // get the <XXXX ... name
            std::string value = node.toElement().getValue();
            TEST_INFO("         '" << value << "'");
        } else {
            // simple debug for other type:
            TEST_INFO("         ** " << node);
        }
    }
    std::string internalData = element.getText();
    
}

void appl::read() {
    readFromFile();
    readFromString1();
    readFromString1();
    readFull();
}