how to use function in php code example

Example 1: function php

function functionName() {
    //code to be executed;
}

Example 2: how to define function in php

<?php
function writeMsg() {
    echo "Hello world!";
}

writeMsg(); //call the function
?>

Example 3: execute function php

function functionName() {
    //code to be executed;
}
functionName();

Example 4: php function

<html>
   
   <head>
      <title>Writing PHP Function with Parameters</title>
   </head>
   
   <body>
   
      <?php
         function addFunction($num1, $num2) {
            $sum = $num1 + $num2;
            echo "Sum of the two numbers is : $sum";
         }
         
         addFunction(10, 20);
      ?>
      
   </body>
</html>