PHP Update Array Items

0
7K

Update Array Item

To update an existing array item, you can refer to the index number for indexed arrays, and the key name for associative arrays.

ExampleGet your own PHP Server

Change the second array item from "BMW" to "Ford":

$cars = array("Volvo", "BMW", "Toyota");
$cars[1] = "Ford";
Try it Yourself »

Note: The first item has index 0.

To update items from an associative array, use the key name:

Example

Update the year to 2024:

$cars = array("brand" => "Ford", "model" => "Mustang", "year" => 1964);
$cars["year"] = 2024;
Try it Yourself »

Update Array Items in a Foreach Loop

There are different techniques to use when changing item values in a foreach loop.

One way is to insert the & character in the assignment to assign the item value by reference, and thereby making sure that any changes done with the array item inside the loop will be done to the original array:

Example

Change ALL item values to "Ford":

$cars = array("Volvo", "BMW", "Toyota");
foreach ($cars as &$x) {
  $x = "Ford";
}
unset($x);
var_dump($cars);
Try it Yourself »

Note: Remember to add the unset() function after the loop.

Without the unset($x) function, the $x variable will remain as a reference to the last array item.

To demonstrate this, see what happens when we change the value of $x after the foreach loop:

Example

Demonstrate the consequence of forgetting the unset() function:

$cars = array("Volvo", "BMW", "Toyota");
foreach ($cars as &$x) {
  $x = "Ford";
}

$x = "ice cream";

var_dump($cars);
Try it Yourself »
Search
Categories
Read More
Other
PHP Comments
Comments in PHP A comment in PHP code is a line that is not executed as a part of the program....
By PHP Tutorial 2024-05-17 07:14:49 0 6K
Other
PHP Variables Scope
PHP Variables Scope In PHP, variables can be declared anywhere in the script. The scope of a...
By PHP Tutorial 2024-05-17 07:18:52 0 10K
Other
PHP while Loop
The while loop - Loops through a block of code as long as the specified condition is...
By PHP Tutorial 2024-05-17 07:48:58 0 4K
Other
PHP $GLOBALS
$GLOBALS is an array that contains all global variables. Global Variables Global...
By PHP Tutorial 2024-05-17 08:08:27 0 7K
Other
PHP Operators
PHP Operators Operators are used to perform operations on variables and values. PHP divides the...
By PHP Tutorial 2024-05-17 07:41:39 0 9K
Sociallez https://sociallez.com