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);
?>
$a=array("a"=>"Cat","b"=>"Dog");
array_unshift($a,"Horse");
print_r($a);
?>
Array ( [0] => Horse [a] => Cat [b] => Dog )
Example 2
Return value:
<?php
$a=array("a"=>"Cat","b"=>"Dog");
print_r(array_unshift($a,"Horse"));
?>
$a=array("a"=>"Cat","b"=>"Dog");
print_r(array_unshift($a,"Horse"));
?>
3
Example 3
Numeric keys:
<?php
$a=array(0=>"Cat",1=>"Dog");
array_unshift($a,"Horse");
print_r($a);
?>
$a=array(0=>"Cat",1=>"Dog");
array_unshift($a,"Horse");
print_r($a);
?>
Array ( [0] => Horse [1] => Cat [2] => Dog )