It’s a good practice to separate back end logic (PHP) from front end markup (HTML). That isn’t always possible or the best choice, especially if you are working on a small web application. Here’s some of the ways to cleanly integrate HTML into PHP.

Times to use this

As I said above, separating the back end logic from the front end markup is a great practice. I don’t always do this, though. Unless you’re using a template engine, such as Smarty, it isn’t always practical to separate the back end from the front end. You still should if the project is large enough, but if it isn’t it’s not worth it in my mind.

When I described my method of organization for most projects, I had a directly called ‘elements’ that contained all of the front end elements. The scripts in that folder still contain logic, though. I don’t use a template engine, so it’s impossible to have completely segregate the logic from the markup.

Integrating HTML

Instead, here’s a few ways to integrate HTML into your PHP logic while still keeping things clean.

Double quotes and braces

This is probably the method that I use most often. Here’s an example:

echo "<div>{$variableOne}</div>";
echo "<div class=\"class_one\">{$variableTwo}</div>";
echo "<div class=\"class_two\">{$variableThree} to {$variableFour}</div>";

I find that this is really clean and easy to scan. It’s easy to see the variables in the code since they all begin with {$ and end with }. I also use code highlighting, so that helps.

Single quotes and concatenation

This is another popular method. The speeds of this method and the previous have been debated, but I don’t think that it really matters. The difference is in nano seconds. If you really want to optimize things, there are a lot more changes that you could make that would have more of an effect than switching between single quotes and double quotes.

echo '<div>' . $variableOne . '</div>';
echo '<div class="class_one">' . $variableTwo . '</div>';
echo '<div class="class_two"> ' . $variableThree . ' to ' . $variableFour . '</div>';

An advantage of this method is that you don’t have to escape double quotes that may appear in HTML. I find this method harder to read than the previous, especially if there are short strings between variables. It’s hard to quickly tell the difference between $variableThree . ' to ' . $variableFour and $variableThree . 'to' . $variableFour, especially if you include spaces between the periods as I do.

Jump out of PHP

This method is most popular for large blocks of code. It can great really repetitive to just keep outputting HTML from PHP, so why not just write the HTML and then add in the PHP where necessary?

<div>
	<?php echo $variableOne; ?>
</div>
<div class="class_one">
	<?php echo $variableTwo; ?>
</div>
<div class="class_two">
	<?php echo $variableThree; ?> to <?php echo $variableFour; ?>
</div>

An advantage of this method is that it’s much easier to retain the indent structure of HTML. A disadvantage is that it can get repetitive to keep using to output variables. It’s possible to use the shorthand , but that may not work on all servers. It also doesn’t work as well if you have a lot of logic and conditional statements instead of just variables.

A combination of them all

The best choice is probably to just use all of these methods as needed. You should decide on whether you will use single quotes or double quotes and then be consistent with your decision. Then, jump out of PHP where needed and use single quotes or double quotes where needed. Here’s an example of a combination:

<div>
	<?php echo $variableOne; ?>
</div>
<div class="class_one">
	<?php echo $variableTwo; ?>
</div>
<div class="class_two">
	<?php echo "{$variableThree} to {$variableFour}"; ?>
</div>

Since it feels really redundant to jump into PHP, echo a variable, jump out of PHP, output a string, jump back into PHP, echo another variable, jump back out of PHP, I combined that part to just use double quotes. This method probably best represents the way that I code. I may have used double quotes for this, since it would only be three lines, but for the example I expanded it and then added in the PHP.

What about you?

What methods do you use to integrate HTML into PHP? Do you use any methods other than the ones listed here? Please leave a comment, I look forward to hearing your thoughts!

(thumbnail by f-l-e-x, banner by Powerhouse Museum)

Tags: Clean Code, Code Organization, Integrate HTML Into PHP, Web Development