Question

Is it bad practice using require() a lot? Most websites have a header and a footer that looks the same whereever you navigate on the page. But the main content varies from page to page. And since I don´t want to reuse code, have the same code in two places, I think require() is pretty good. But is it okay using it like I do?

Here´s my example:

<div class="content">
    <section>
        <?php require('mainpage.php'); ?>
    </section>
    <aside class="sidebar">
        <div class="sidebar-box">
            <?php require('sidebar/box1.php'); ?>
        </div>
        <div class="sidebar-box">
            <?php require('sidebar/box2.php'); ?>
        </div>
    </aside>
</div>

A sidebar box is a box that contains stuff like “Latest news” etc. And since I may want to have the “Latest news” box on many pages I need to require() it in order to not have the same code in two places.

Should I solve it someway else?

Thanks for your help!

Answer 1

Nothing wrong with that at all, it’s very good practice to reuse code chunks. It also keep the HTML structure far more readable and gives you some basic separation between HTML presentation and PHP business logic. Check out the MVC pattern for why this is a good thing.

Some points to bear in mind:

• You might want to consider using a $docroot variable that has the full server file path, as relative file paths can occasionally go wonky on some PHP installs and also if you include the above code itself from another file. Relative file paths look like it’s easier to move the whole codebase around, but you can just alter $docroot if you do this and it’s fine. You could also use a $librarydir variable so that your HTML templates can be moved around without shifting the location of the PHP files.
• Some files ought to be brought it with require_once() so that you don’t get a mess e.g. the HTML header, page footer etc. Might sound obvious, but it’s easy to put the footer into two files that you then include from somewhere else, so this can make debugging easier by giving a more verbose error message.
• You may find that a templating engine which does the MVC approach in a more formalised an flexible way could help you. Check out Smarty as others have mentioned, or Dwoo, which is a PHP5 rewrite of it.
• Odd things can happen if the code in the included files uses variables in the global scope, and as your program becomes more complex, this can lead to hard-to-pin-down bugs where one include is subtly breaking another by altering variables with the same name. Consider putting the code for a sideblock into a function or class so that variables are in their own scope and you can keep them separate.