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PHP in a Nutshell
book

PHP in a Nutshell

by Paul Hudson
October 2005
Intermediate to advanced content levelIntermediate to advanced
372 pages
11h 35m
English
O'Reilly Media, Inc.
Content preview from PHP in a Nutshell

Name

array_diff()

Synopsis

    array array_diff ( array arr1, array arr2 [, array ...] )

The array_diff() function returns a new array containing all the values of array $arr1 that do not exist in array $arr2.

    $toppings1 = array("Pepperoni", "Cheese", "Anchovies", "Tomatoes");
    $toppings2 = array("Ham", "Cheese", "Peppers");
    $diff_toppings = array_diff($toppings1, $toppings2);

    var_dump($diff_toppings);
    // prints: array(3) { [0]=> string(9) "Pepperoni" [2]=>
    // string(9) "Anchovies" [3]=> string(8) "Tomatoes" }

You can diff several arrays simultaneously by providing more parameters to the function. In this situation, the function will return an array of values in the first array that do not appear in the second and subsequent arrays. For example:

    $arr1_unique = array_merge($arr1, $arr2, $arr3, $arr4);
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Publisher Resources

ISBN: 0596100671Errata Page