ZEND PHP 5 Certification STUDY GUIDE

Arrays ” 69
In this example, we use array_shift() to push the first element out of the array. Next,
using array_unshift(), we do the reverse and add a value to the beginning of the
array. This example results in:
array(2) {
[0]=>
string(3) "bar"
[1]=>
string(3) "baz"
}
array(3) {
[0]=>
string(3) "foo"
[1]=>
string(3) "bar"
[2]=>
string(3) "baz"
}
Set Functionality
Some PHP functions are designed to perform set operations on arrays. For example,
array_diff() is used to compute the difference between two arrays:
$a = array (1, 2, 3);
$b = array (1, 3, 4);
var_dump (array_diff ($a, $b));
The call to array_diff() in the code above will cause all the values of $a that do not
also appear in $b to be retained, while everything else is discarded:
Licensed to 482634 - Amber Barrow (itsadmin@deakin.edu.au)
array(1) {
[1]=>
int(2)
}
Note that the keys are ignored—if you want the difference to be computed based
on key-value pairs, you will have to use array_diff_assoc() instead, whereas if you