PHP Update Array Items

0
5K

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 Functions
The real power of PHP comes from its functions. PHP has more than 1000 built-in functions, and...
By PHP Tutorial 2024-05-17 07:53:06 0 3K
Other
PHP - Modify Strings
PHP has a set of built-in functions that you can use to modify strings. Upper Case...
By PHP Tutorial 2024-05-17 07:29:19 0 6K
Other
PHP if Statements
Conditional statements are used to perform different actions based on different conditions....
By PHP Tutorial 2024-05-17 07:45:23 0 3K
Other
PHP Multiline Comments
Multi-line Comments Multi-line comments start with /* and end with */. Any text...
By PHP Tutorial 2024-05-17 07:15:48 0 4K
Other
PHP Delete Array Items
Remove Array Item To remove an existing item from an array, you can use...
By PHP Tutorial 2024-05-17 08:06:22 0 5K