PHP Default Argument Values Function

ᴰᵒᵖᵖᵉˡᵍᵃⁿᵍᵉʳ 多佩尔甘格尔

PHP allows you to define C++ style default argument values. In such case, if you don't pass any value to the function, it will use default argument value.

Let' see the simple example of using PHP default arguments in function.

Example 1

<?php  
function sayHello($name="Ram"){  
echo "Hello $name<br/>";  
}  
sayHello("Sonoo");  
sayHello();//passing no value  
sayHello("Vimal");  
?>  

Output:

Hello Sonoo

Hello Ram

Hello Vimal

Since PHP 5, you can use the concept of default argument value with call by reference also.

Example 2

<?php    
function greeting($first="Sonoo",$last="Jaiswal"){    
echo "Greeting: $first $last<br/>";    
}    
greeting();  
greeting("Rahul");  
greeting("Michael","Clark");  
?>    

Output:

Greeting: Sonoo Jaiswal

Greeting: Rahul Jaiswal

Greeting: Michael Clark

Example 3

<?php  
function add($n1=10,$n2=10){  
$n3=$n1+$n2;  
echo "Addition is: $n3<br/>";  
}  
add();  
add(20);  
add(40,40);  
?>  

Output:

Addition is: 20

Addition is: 30

Addition is: 80