{"id":71,"date":"2021-03-08T00:11:58","date_gmt":"2021-03-08T00:11:58","guid":{"rendered":"https:\/\/phptutorial.net\/?page_id=71"},"modified":"2025-04-06T02:04:08","modified_gmt":"2025-04-06T02:04:08","slug":"php-functions","status":"publish","type":"page","link":"https:\/\/www.phptutorial.net\/php-tutorial\/php-functions\/","title":{"rendered":"PHP Functions"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you will learn about PHP functions and how to define user-defined functions.<\/p>\n\n\n\n

What is a function #<\/a><\/h2>\n\n\n\n

A function is a named block of code that performs a specific task.<\/p>\n\n\n\n

So far, you have learned how to use built-in functions in PHP, such as var_dump()<\/a><\/code> that dumps information about a variable.<\/p>\n\n\n\n

In this tutorial, you’ll learn how to define your functions. These functions are called user-defined functions.<\/p>\n\n\n\n

Why do you need functions in the first place? #<\/a><\/h2>\n\n\n\n

Sometimes, you need to perform the same task multiple times in a script. For example, suppose that you want to show a message that welcomes a user like this:<\/p>\n\n\n

<?php<\/span>\n\necho<\/span> 'Welcome!'<\/span>;<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
If you want to show the same message in other places, copy and paste the above statement in many places.<\/p>\n\n\n\n
But when you want to change the message from Welcome!<\/code> to Welcome Back<\/code>! you need to change it in various places. It’ll make the code very difficult to maintain.<\/p>\n\n\n\n
This is where functions come into play. A function allows you to assign a name to a code block and reuse that code block in multiple places without duplicating the code.<\/p>\n\n\n\n
To define and call a user-defined function, you use the following steps:<\/p>\n\n\n\n
First, define a function called welcome()<\/code> like this:<\/p>\n\n\n
<?php<\/span>\n\n\nfunction<\/span> welcome<\/span>()<\/span>\n<\/span>{\n\techo<\/span> 'Welcome!'<\/span>;\n}<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Then, call the welcome()<\/code> function in any place where you want to show the welcome message:<\/p>\n\n\n
<?php<\/span>\n\nfunction<\/span> welcome<\/span>()<\/span>\n<\/span>{\n\techo<\/span> 'Welcome!'<\/span>;\n}\n\nwelcome();<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
Later, if you want a different message, you can change it centrally in the welcome()<\/code> function instead of in multiple places.<\/p>\n\n\n\n
Using a function, you can reuse a code block and make your script easier to maintain.<\/p>\n\n\n\n
Define a function #<\/a><\/h2>\n\n\n\n
To define a function, you use the following syntax:<\/p>\n\n\n
<?php<\/span>\n\nfunction<\/span> function_name<\/span>()<\/span> <\/span>{\n    statement;\n}<\/code><\/span>Code language:<\/span> PHP<\/span> (<\/span>php<\/span>)<\/span><\/small><\/pre>\n\n\n
In this syntax:<\/p>\n\n\n\n
Try it<\/a><\/p>\n\n\n\n
Try it<\/a><\/p>\n\n\n\n