text 保存自https://wpshout.com/learning-php-for-wordpress-development-introduction-to-php-functions/

Posted 2021-04-30

<?php

// First we're going to *define* the say_hello() function
function say_hello() {
	echo 'Hello world!'; // This is what the function will do when called
}

// Now we're going to *call* the say_hello() function
say_hello(); // This will print "Hello world!" into the HTML document

// Uh oh! We're calling a function that isn't defined. We'll get a fatal error if we do this.
say_something_else(); 

?>