Pass by Value and Reference Example in PHP

Hi artisans, in this short article, I’m going to write about the pass by value and pass by reference. I’ll show examples in PHP & will explain simply. Let’s see:

Table of Contents

  1. Pass by Value
  2. Pass by Reference

Pass by Value

“Pass by value” means that we pass the actual value of the variable into a function. Let’s look at the following example:

function function_name($string) {
    $string = "I'm from function";
    print($string);
}

$string = "I'm from outside of function";
function_name($string);
echo "
"; print($string);

The output:

I'm from function
I'm from outside of function

Pass by Reference

“Pass by Reference” means that we pass the variable itself into the function with the value. We need to add & (ampersand) symbol before the variable name. The value of the outside variable will be changed too. Because both variables are defined by the same reference. Have a look at an example:

function function_name(&$string) {
    $string = "I'm from function";
    print($string);
}

$string = "I'm from outside of function";
function_name($string);
echo "
"; print($string);

The output:

I'm from function
I'm from function
That’s all. Thanks for reading. ?

Software Engineer | Ethical Hacker & Cybersecurity...

Md Obydullah is a software engineer and full stack developer specialist at Laravel, Django, Vue.js, Node.js, Android, Linux Server, and Ethichal Hacking.