Here is a short example. Consider the following short XML file (people.xml):

<people>
<person gender="male">Joe</person>
<person gender="female">Judy</person>
</people>

This is the PHP code that accesses and prints the contents of the file (print_people.php):

<?php

$people = simplexml_load_file("people.xml");
foreach ($people->person as $person) {
print $person . " is " . $person["gender"] . "\n";
}

?>

The resulting output of this code is:

Joe is male
Judy is female

The PHP code simply exposes the contents of the XML file as if they were elements in a standard PHP array. By iterating through the array with a simple loop, the content of the XML file is read and the output is created without any need to further parse the XML file.

There has never been an easier way to access and manipulate XML data. If there is some special XML manipulation that needs to be done in DOM, most of the basic work can be done in SimpleXML, and then the result converted to DOM and additional manipulations run without having to write and reread the XML data to some kind of temporary or permanent storage.

Web Services Support
The term Web services describes a standardized way of integrating applications using the XML, SOAP, WSDL, and UDDI open standards over an Internet protocol backbone. Web services allow different applications from different sources to communicate with each other without time-consuming custom coding, and because all communication is in XML, Web services are not tied to any one operating system or programming language. For example, Java can talk with Perl, and Windows applications can talk with UNIX applications.

PHP 5 features new native support for SOAP and WSDL making it incredibly easy to create and consume Web services within the enterprise or on the Internet. For example, all that is required to access a Web service is to point to a relevant WSDL file describing that service and then simply invoke a function exposed in that Web service interface. Only two lines of code are required!

Here is a specific example of the PHP code required to access a Web service exposed on the Internet to print the current stock quote for Microsoft:

<?php

$client = new
SoapClient("http://services.xmethods.net/soap/urn:xmethods-delayed-quotes.wsdl");

print($client->getQuote("MSFT"));

?>

All that was required was to create an object by passing in the relevant WSDL, and then access a function in the Web service by invoking a method within the object.

It's similarly easy to publish Web services. The services are implemented as PHP-based classes, and then described in a WSDL file. PHP 5 has built-in capabilities to publish that service, provide the WSDL on request, and execute the functionality and return a result (if needed) when invoked.

Rapid Prototyping and Assembly Using Web Services
The seamless XML and Web services support in PHP 5 enable a developer to quickly prototype and deliver applications that assemble together capabilities exposed via Web services. The developer doesn't need to focus on the details of parsing XML files and piecing together SOAP messages. Rather, the developer can focus on the business needs being addressed by the application. This results in rapid development, early prototyping and feedback, frequent iteration, and a robust resulting application.

PHP Integration with Existing Code and Data
In addition to support for emerging standards like XML and Web services, PHP provides a comprehensive set of interfaces with existing code libraries and databases that may exist within an enterprise. This makes PHP ideally suited to exploit functionality and data in these various environments, and to expose them to other applications or enterprises using Web services. PHP provides integration with C/C++, COM/.NET, Java, Perl, and SQL databases.

C/C++ and COM/.NET
PHP is written in C, and has a powerful extension interface allowing new capabilities to be added to the language using C and C++. It has equally powerful capabilities to allow PHP code to connect with existing libraries written in C/C++, as well as COM and .NET on the Microsoft Windows platform.

Microsoft COM (Component Object Model) defines a common calling convention that enables code written in any language to call and interoperate with code written in any other language. Microsoft .NET is an overall strategy for providing individuals and businesses with a seamlessly interoperable and Web-enabled interface for applications and computing devices based on XML and Web services. It supports over 20 programming languages and allows for interoperability between these languages. Microsoft intends to offer a range of Web-based services and application building blocks via .NET.

COM and .NET access are built in to PHP 5 and are available to any PHP code running on the Microsoft Windows platform. The COM class in PHP allows you to instantiate a COM object, call its methods, and access its properties. The DOTNET class allows you to instantiate a class from a .NET assembly, call its methods, and access its properties. PHP does this via the COM interoperability layer for .NET. In implementation terms, PHP sees .NET objects as though they were COM objects.

Java
Zend Technologies is working with Sun Microsystems on JSR 223, a specification to describe how to write portable Java classes that can be invoked from a page written in any scripting language, with PHP serving as the reference scripting language implementation. Through this specification and reference implementation, it's very straightforward to invoke Java code directly from PHP, enabling existing Java code libraries and application functionality to be incorporated into PHP applications.