Pro PHP- Patterns, Frameworks, Testing and More

CHAPTER 10 ■ SPL ITERATORS^159

<book>

<name>Other Book</name>

</book>

</library>

The SimpleXMLIterator is a RecursiveIterator that allows you to access all the nodes within

an XML document. The example in Listing 10-17 uses the recursive nature of the iterator to

create a listing of books and their elements in the test.xml file.

Listing 10-17. Using the SimpleXML Iterator

$it = new SimpleXMLIterator(file_get_contents('test.xml'));

foreach($it as $key=>$node) {

echo $key. "\n";

if($it->hasChildren()) {

foreach($it->getChildren() as $element=>$value) {

echo "\t". $element. ":". $value ."\n";

}

}

}

book

name:Pro PHP

author:Kevin McArthur

book

name:Other Book

The hasChildren() condition is not required, but is included for demonstration. Without

hasChildren(), getChildren() will simply return no elements and the foreach loop would not

be entered.

Accessing Flat-File Databases with DBA

The DBA extension provides access to many useful flat-file format databases, like the popular

DB4 format. The DBA iterators are useful for accessing data exposed by the DBA extension. The

following examples use the .ini file handler, but several other handlers are available. To build

PHP with the DBA extension with .ini file and cdb drivers enabled, you must include the

following in your PHP configure line:

--enable-dba --with-inifile

■Note Many package-managed installations of PHP will include some support for DBA. Its presence, as

well as the existence of specific drivers, is exposed via phpinfo().

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