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PHP array_pad() Function

Definition and Usage

The array_pad() function inserts a specified number of elements, with a specified value, to an array.

array_pad(array,size,value)

Parameter	Description
array	Required. Specifies an array
size	Required. Specifies the number of elements in the array returned from the function
value	Required. Specifies the value of the new elements in the array returned from the function

Tip: If you assign a negative size parameter, the function will insert new elements BEFORE the original elements. (See example 2)

Note: This function will not delete any elements if the size parameter is less than the original array's size.

<?php
$a=array("Dog","Cat");
print_r(array_pad($a,5,0));
?>

The output of the code above will be:

Array ( [0] => Dog [1] => Cat [2] => 0 [3] => 0 [4] => 0 )

With a negative size parameter:

<?php
$a=array("Dog","Cat");
print_r(array_pad($a,-5,0));
?>

The output of the code above will be:

Array ( [0] => 0 [1] => 0 [2] => 0 [3] => Dog [4] => Cat )