Podręcznik PHP
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# XCVIII. SimpleXML functions

# Wprowadzenie

Ostrzeżenie
Ten moduł jest w stadium EKSPERYMENTALNYM. Oznacza to, że zachowanie tych funkcji, ich nazwy, w zasadzie wszystko udokumentowane tutaj może zostać zmienione w przyszłych wersjach PHP bez wcześniejszego uprzedzenia. Używaj tego modułu na własne ryzyko.

The SimpleXML extension provides a very simple and easily usable toolset to convert XML to an object that can be processed with normal property selectors and array iterators.

# Instalacja

This extension is only available if PHP was configured with `--enable-simplexml`. The PHP configuration script does this by default.

# Przykłady

Many examples in this reference require an XML string. Instead of repeating this string in every example, we put it into a file which we include in each example. This included file is shown in the following example section. Alternatively, you could create an XML document and read it with simplexml_load_file().

Przykład 1. Include file example.php with XML string

`<?php
$xmlstr = <<<XML
<?xml version='1.0' standalone='yes'?>
<movies>
<movie>
<title>PHP: Behind the Parser</title>
<characters>
<character>
<name>Ms. Coder</name>
<actor>Onlivia Actora</actor>
</character>
<character>
<name>Mr. Coder</name>
<actor>El Act&oacute;r</actor>
</character>
</characters>
<plot>
So, this language. It's like, a programming language. Or is it a
scripting language? All is revealed in this thrilling horror spoof
of a documentary.
</plot>
<rating type="thumbs">7</rating>
<rating type="stars">5</rating>
</movie>
</movies>
XML;
?>`

The simplicity of SimpleXML appears most clearly when one extracts a string or number from a basic XML document.

Przykład 2. Getting `<plot>`

`<?php include 'example.php'; $xml = simplexml_load_string($xmlstr); echo $xml->movie[0]->plot; // "So this language. It's like..." ?>`

Przykład 3. Accessing non-unique elements in SimpleXML

When multiple instances of an element exist as children of a single parent element, normal iteration techniques apply.

`<?php include 'example.php'; $xml = simplexml_load_string($xmlstr); /* For each <movie> node, we echo a separate <plot>. */ foreach ($xml->movie as $movie) { echo $movie->plot, '<br />'; } ?>`

Przykład 4. Using attributes

So far, we have only covered the work of reading element names and their values. SimpleXML can also access element attributes. Access attributes of an element just as you would elements of an array.

`<?php include 'example.php'; $xml = simplexml_load_string($xmlstr); /* Access the <rating> nodes of the first movie. * Output the rating scale, too. */ foreach ($xml->movie[0]->rating as $rating) { switch($rating['type']) { // Get attributes as element indices case 'thumbs': echo $rating, ' thumbs up'; break; case 'stars': echo $rating, ' stars'; break; } } ?>`

Przykład 5. Using Xpath

SimpleXML includes builtin Xpath support. To find all `<character>` elements:

`<?php include 'example.php'; $xml = simplexml_load_string($xmlstr); foreach ($xml->xpath('//character') as $character) { echo $character->name, 'played by ', $character->actor, '<br />'; } ?>`

'`//`' serves as a wildcard. To specify absolute paths, omit one of the slashes.

Przykład 6. Setting values

Data in SimpleXML doesn't have to be constant. The object allows for manipulation of all of its elements.

`<?php include 'example.php'; $xml = simplexml_load_string($xmlstr); $xml->movie[0]->actor[0]->age = '21'; echo $xml->asXML(); ?>`

The above code will output a new XML document, just like the original, except that the new XML will define Ms. Coder's age as 21.

Przykład 7. DOM Interoperability

PHP has a mechanism to convert XML nodes between SimpleXML and DOM formats. This example shows how one might change a DOM element to SimpleXML.

`<?php $dom = new domDocument; $dom->loadXML('<books><book><title>blah</title></book></books>'); if (!$dom) { echo 'Error while parsing the document'; exit; } $s = simplexml_import_dom($dom); echo $s->book[0]->title; ?>`

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