PHP SimpleXML Parser
SimpleXML is a PHP extension that allows us to easily manipulate and get XML data.
The SimpleXML Parser
SimpleXML is a tree-based parser.
SimpleXML provides an easy way of getting an element's name, attributes and textual content if you know the XML document's structure or layout.
SimpleXML turns an XML document into a data structure you can iterate through like a collection of arrays and objects.
Compared to DOM or the Expat parser, SimpleXML takes a fewer lines of code to read text data from an element.
Installation
As of PHP 5, the SimpleXML functions are part of the PHP core. No installation is required to use these functions.
PHP SimpleXML - Read From String
The PHP simplexml_load_string() function is used to read XML data from a string.
Assume we have a variable that contains XML data, like this:
$myXMLData =
"<?xml version='1.0' encoding='UTF-8'?>
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>";
The example below shows how to use the simplexml_load_string() function to read XML data from a string:
Example
<?php
$myXMLData =
"<?xml version='1.0' encoding='UTF-8'?>
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>";
$xml=simplexml_load_string($myXMLData) or die("Error: Cannot create
object");
print_r($xml);
?>
The output of the code above will be:
SimpleXMLElement Object ( [to] => Tove [from] => Jani [heading] => Reminder
[body] => Don't forget me this weekend! )
Error Handling Tip: Use the libxml functionality to retrieve all XML errors when loading the document and then iterate over the errors. The following example tries to load a broken XML string:
Example
<?php
libxml_use_internal_errors(true);
$myXMLData =
"<?xml
version='1.0' encoding='UTF-8'?>
<document>
<user>John Doe</wronguser>
<email>john@example.com</wrongemail>
</document>";
$xml = simplexml_load_string($myXMLData);
if ($xml
=== false) {
echo "Failed loading XML: ";
foreach(libxml_get_errors() as $error) {
echo "<br>", $error->message;
}
} else {
print_r($xml);
}
?>
The output of the code above will be:
Failed loading XML:
Opening and ending tag mismatch: user line 3 and
wronguser
Opening and ending tag mismatch: email line 4 and wrongemail
PHP SimpleXML - Read From File
The PHP simplexml_load_file() function is used to read XML data from a file.
Assume we have an XML file called "note.xml", that looks like this:
<?xml version="1.0" encoding="UTF-8"?>
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>
The example below shows how to use the simplexml_load_file() function to read XML data from a file:
Example
<?php
$xml=simplexml_load_file("note.xml") or die("Error: Cannot create
object");
print_r($xml);
?>
The output of the code above will be:
SimpleXMLElement Object ( [to] => Tove [from] => Jani [heading] => Reminder
[body] => Don't forget me this weekend! )
Tip: The next chapter shows how to get/retrieve node values from an XML file with SimpleXML!
More PHP SimpleXML
For more information about the PHP SimpleXML functions, visit our PHP SimpleXML Reference.