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PHP array_splice() Function

Definition and Usage

The array_splice() function removes selected elements from an array and replaces it with new elements. The function also returns an array with the removed elements.

Syntax

array_splice(array,start,length,array)

Parameter	Description
array	Required. Specifies an array
start	Required. Numeric value. Specifies where the function will start removing elements. 0 = the first element. If this value is set to a negative number, the function will start that far from the last element. -2 means start at the second last element of the array.
length	Optional. Numeric value. Specifies how many elements will be removed, and also length of the returned array. If this value is set to a negative number, the function will stop that far from the last element. If this value is not set, the function will remove all elements, starting from the position set by the start-parameter.
array	Optional. Specifies an array with the elements that will be inserted to the original array. If it's only one element, it can be a string, and does not have to be an array.

Tips and Notes

Tip: If the function does not removes any elements (length=0), the replacement array will be inserted from the position of the start parameter. (See example 3)

Note: The keys in the replacement array are not preserved.

Example 1

<?php
$a1=array(0=>"Dog",1=>"Cat",2=>"Horse",3=>"Bird");
$a2=array(0=>"Tiger",1=>"Lion");
array_splice($a1,0,2,$a2);
print_r($a1);
?>

The output of the code above will be:

Array ( [0] => Tiger [1] => Lion [2] => Horse [3] => Bird )

Example 2

The same example as example 1, but the output is the returned array:

<?php
$a1=array(0=>"Dog",1=>"Cat",2=>"Horse",3=>"Bird");
$a2=array(0=>"Tiger",1=>"Lion");
print_r(array_splice($a1,0,2,$a2));
?>

The output of the code above will be:

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

Example 3

With the length parameter set to 0:

<?php
$a1=array(0=>"Dog",1=>"Cat");
$a2=array(0=>"Tiger",1=>"Lion");
array_splice($a1,1,0,$a2);
print_r($a1);
?>

The output of the code above will be:

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

Complete PHP Array Reference