array_unshift

Definition and usage

array_unshift() function is used to insert new elements into an array. The value of the new array will be inserted at the beginning of the array.

The added elements are added as a whole, the order in the array is the same as in the parameters.

This function returns the number of elements in the array.

Tip: You can insert one or more values.

Note: The numeric key names will start at 0 and increment by 1. The string key name will remain unchanged.

Example

Example 1

Insert the element "blue" into the array:

 <?php
$a = array ( "a" => "red" , "b" => "green" ) ;
array_unshift ( $a , "blue" ) ;
print_r ( $a ) ;
?>

Try it yourself

Example 2

Show return value:

 <?php
$a = array ( "a" => "red" , "b" => "green" ) ;
print_r ( array_unshift ( $a , "blue" ) ) ;
?>

Try it yourself

Example 3

Use the numeric key name:

 <?php
$a = array ( 0 => "red" , 1 => "green" ) ;
array_unshift ( $a , "blue" ) ;
print_r ( $a ) ;
?>

Try it yourself

grammar

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