Amyst Design Company, web and print design and development services

Anyone who has done serious work with PHP since 5.0 knows the way to stay future proof is to adopt and love like it was your own the object oriented programming model. This little snippet has gone a LONG way to making my life easier. To use it, simply include it in your globally included functions library (yes, functions not objects.. regular every day function methods).

In the snippet below there is a constant “PATH_CLASSES”, in my global definitions I have this defined as the absolute path to my class libraries which are all in the same directory for this purpose.

function __autoload( $class_name )
{
	$file_formats = array('%s.php', '%s.class.php', 'class.%s.php', '%s.inc.php');
	foreach ( $file_formats as $file_format )
	{
		$file = PATH_CLASSES.sprintf($file_format, strtolower($class_name));
		if ( file_exists($file) ) require_once($file);
	}
	return;
}

While developing a new project management application I needed a way to search an array of objects for a specific object property value. For example, I had an array of “employee” objects that contain a great many properties to describe each “employee” and you want to search this array for an employee object that has a specific value for one of it’s properties. To solve this I have come up with the following little snippet:

function search_object_array($needle_key, $needle_val, $haystack)
{
	// iterate through our haystack
	for ( $i = 0; $i < count($haystack); $i++ )
	{
		// ensure this array element is an object and has a key that matches our needle's key
		if ( is_object($haystack[$i]) and property_exists($haystack[$i], $needle_key) )
		{
			// determine if comparison is case sensitive
			if ( strtolower($needle_val) == strtolower($haystack[$i]->$needle_key) ) return $i;
		}
	}
	// no match found
	return false;
}

This function returns the index of the object array if a match is found and false if no matches are found.

So lets test it.
First I’ll define a class that we will use to generate our objects that will populate our array, well call this class “foo”.

class foo
{
	public $id;
	public $name;
	public $description;

	public function __construct( $id, $name, $description )
	{
		$this->id = $id;
		$this->name = $name;
		$this->description = $description;
	}
}

Next we’ll populate our object array “$obj_arr” with objects

$obj_arr[0] = new foo(1, 'Joe', 'Joes description');
$obj_arr[1] = new foo(2, 'Sara', 'Saras description');
$obj_arr[2] = new foo(3, 'Adam', 'Adams description');
$obj_arr[3] = new foo(4, 'Jake', 'Jakes description');
$obj_arr[4] = new foo(5, 'Sally', 'Sallys description');
$obj_arr[5] = new foo(6, 'Paul', 'Pauls description');
$obj_arr[6] = new foo(7, 'Freddie', 'Freddies description');

Now lets search our new array of objects for an object that matches our criteria:

$result = search_object_array('name', 'sally', $obj_arr);
echo $result;
// will print: 4

I hope this helps!