PHP Shorthand If / Else Examples

An essential part of programming is evaluating conditions using if/else and switch/case statements. If / Else statements are easy to code and global to all languages. If / Else statements are great but they can be too long.

I preach a lot about using shorthand CSS and using MooTools to make JavaScript relatively shorthand, so I look towards PHP to do the same. If/Else statements aren't optimal (or necessary) in all situations. Enter ternary operators.

Ternary operator logic is the process of using "(condition) ? (true return value) : (false return value)" statements to shorten your if/else structures.

Tips for Using Ternary Operators

Here are a few tips for when using "?:" logic:

Don't go more levels deep than what you feel comfortable with maintaining.
If you work in a team setting, make sure the other programmers understand the code.
PHP.net recommends avoiding stacking ternary operators. "Is [sic] is recommended that you avoid "stacking" ternary expressions. PHP's behaviour when using more than one ternary operator within a single statement is non-obvious."
If you aren't experienced with using ternary operators, write your code using if/else first, then translate the code into ?'s and :'s.
Use enough parenthesis to keep your code organized, but not so many that you create "code soup."

More Sample Usage

Here are a couple more uses of ternary operators, ranging from simple to advanced:

Basic True / False Declaration

$is_admin = ($user['permissions'] == 'admin' ? true : false);

Conditional Welcome Message

echo 'Welcome '.($user['is_logged_in'] ? $user['first_name'] : 'Guest').'!';

Conditional Items Message

echo 'Your cart contains '.$num_items.' item'.($num_items != 1 ? 's' : '').'.';

Conditional Error Reporting Level

error_reporting($WEBSITE_IS_LIVE ? 0 : E_STRICT);

Conditional Basepath

echo '';

Nested PHP Shorthand

echo 'Your score is: '.
($score > 10 ? ($age > 10 ? 'Average' : 'Exceptional') : ($age > 10 ? 'Horrible' : 'Average') );

Leap Year Check

$is_leap_year = ((($year % 4) == 0) && ((($year % 100) != 0) || (($year %400) == 0)));

Conditional PHP Redirect

header('Location: '.($valid_login ? '/members/index.php' : 'login.php?errors=1')); exit();