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PHP array_unshift() Function

Definition and Usage

The array_unshift() function inserts new elements to an array. The new array values will be inserted in the beginning of the array. The function's return value is the new number of elements in the array (See example 2).

Syntax

array_unshift(array,value1,value2,value3...)

Parameter	Description
array	Required. Specifying an array
value1	Required. Specifies a value to insert
value2	Optional. Specifies a value to insert
value3	Optional. Specifies a value to insert

Tips and Notes

Tip: You can add one value, or as many as you like.

Note: Numeric keys will start at 0 and increas by 1 (See example3). String keys will remain the same (See example 1).

Example 1

<?php
$a=array("a"=>"Cat","b"=>"Dog");
array_unshift($a,"Horse");
print_r($a);
?>

The output of the code above will be:

Array ( [0] => Horse [a] => Cat [b] => Dog )

Example 2

Return value:

<?php
$a=array("a"=>"Cat","b"=>"Dog");
print_r(array_unshift($a,"Horse"));
?>

The output of the code above will be:

Example 3

Numeric keys:

<?php
$a=array(0=>"Cat",1=>"Dog");
array_unshift($a,"Horse");
print_r($a);
?>

The output of the code above will be:

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

Complete PHP Array Reference