How to Reset Array in PHP

  1. Use the array_diff() Function to Reset Array in PHP
  2. Use the unset() Function to Reset an Array in PHP

This article will introduce different methods to reset an array in PHP.

Use the array_diff() Function to Reset Array in PHP

In PHP, we can use the array_diff() function to reset an array. This function computes the difference of a given array with another array. The correct syntax to use this function is as follows.

array_diff($array, $Arr1, $Arr2, ...,$ArrN);

The function array_diff() accepts N+1 parameters. The detail of its parameters is as follows.

Parameters Description
$array mandatory It is the main array from which we want to remove a value.
$Arr1, $Arr2, $ArrN mandatory It is the array that we want to remove. The function will take its difference with the array and remove it from the array if it is present.

The program that clears array values is as follows.

<?php
$array = array("Rose","Lili","Jasmine","Hibiscus","Daffodil","Daisy");
echo("Array before deletion: \n");
var_dump($array);
$array = array_diff( $array, $array);
echo("Array after deletion: \n");
var_dump($array);
?>

Output:

Array before deletion: 
array(6) {
  [0]=>
  string(4) "Rose"
  [1]=>
  string(4) "Lili"
  [2]=>
  string(7) "Jasmine"
  [3]=>
  string(8) "Hibiscus"
  [4]=>
  string(8) "Daffodil"
  [5]=>
  string(5) "Daisy"
}
Array after deletion: 
array(0) {
}

Use the unset() Function to Reset an Array in PHP

We will use the unset() function to clear array values. The unset() functions resets a variable. The correct syntax to use this function is as follows.

unset($variable1, $variable2, ..., $variableN);

The built-in function unset() has N parameters. The details of its parameters are as follows.

Parameters Description
$variable1, $variable2, $variableN mandatory It is the variable or data structure that we want to unset. At least one variable is mandatory.

This function returns nothing.

The program below shows the way by which we can use the unset() function to clear array values in PHP.

<?php
$array = array("Rose","Lili","Jasmine","Hibiscus","Daffodil","Daisy");
echo("Array before deletion: \n");
var_dump($array);
unset($array);
echo("Array after deletion: \n");
var_dump($array);
?>

Output:

Array before deletion: 
array(6) {
  [0]=>
  string(4) "Rose"
  [1]=>
  string(4) "Lili"
  [2]=>
  string(7) "Jasmine"
  [3]=>
  string(8) "Hibiscus"
  [4]=>
  string(8) "Daffodil"
  [5]=>
  string(5) "Daisy"
}
Array after deletion: 
NULL

Related Article - PHP Array

  • How to Delete an Element From an Array in PHP