Creating simple function
<?php
function display()
{
echo "hello its working";
}
display();
?>
Output
Passing parameters to functions in php
<?php
//function in php
function display($input)
{
echo "Received the value ".$input;
}
$value=2;
display($value);
?>
Output
Passing multiple parameters to function
<?php
//function in php
function display($input1,$input2)
{
echo "Received the value ".$input1 ." ".$input2;
}
display(3,2);
?>
Output
Returning value from a function using return statment
<?php
//function in php
function display($input1,$input2)
{
return $input1+$input2;
}
$result = display(3,2);
echo $result;
?>
Output
Default parameter for a function in PHP
function display($value=10)
{
echo $value;
}
display();
?>
output 10
Default Paramenter with an argument
<?php
function display($value=10)
{
echo $value;
}
display(25);
?>
Output 25
Enforcing data type strictness for a function in PHP
declare(strict_types=1);
what will be output in this case
<?php
function display($input)
{
echo $input*2;
}
display("satish");
?>
output
Warning: A non-numeric value encountered in C:\xampp\htdocs\iwp\test.php on line 4
Demo code for enforcing data type strictness in PHP
<?php declare(strict_types=1);
function display(int $input)
{
echo $input*2;
}
display(3);
?>
Output
Making a function accept only a String Datatype as input
<?php declare(strict_types=1);
function display(string $input)
{
echo $input;
}
display("satish");
?>
Output satish
Enforcing a strict datatype return from a function
returning an int instead of a string
<?php declare(strict_types=1);
function display(string $input):string
{
return 2;
}
$result = display("Satish");
echo $result;
?>
Output
Fatal error: Uncaught TypeError: Return value of display() must be of the type string, integer returned in C:\xampp\htdocs\iwp\test.php:4 Stack trace: #0 C:\xampp\htdocs\iwp\test.php(7): display('Satish') #1 {main} thrown in C:\xampp\htdocs\iwp\test.php on line 4
Demo for pass by value to a function
<?php
function change($input)
{
$input++;
echo "value inside the function".$input;
}
$value=2;
change($value);
echo "value after calling the function". $value;
?>
Output
Demo code for pass by reference to a function
<?php
function change(&$input)
{
$input++;
echo "value inside the function".$input;
}
$value=2;
change($value);
echo "value after calling the function". $value;
?>
Output