Alternative syntax for control structures

PHP offers an alternative syntax for some of its control structures; namely, if, while, for, foreach, switch, and declare. In each case, the basic form of the alternate syntax is to change the opening brace to a colon (:) and the closing brace to endif;, endwhile;, endfor;, endforeach;, endswitch;, or enddeclare;, respectively.

<?php
$a = 5;
if ($a == 5): ?>
A is equal to 5
<?php endif; ?>

   

A is equal to 5

In the above example, the HTML block "A is equal to 5" is nested within an if statement written in the alternative syntax. The HTML block would be displayed only if $a is equal to 5.

The alternative syntax applies to else and elseif as well. The following is an if structure with elseif and else in the alternative format:

<?php
$a = 5;
if ($a == 5):
    echo "a equals 5";
    echo "...";
elseif ($a == 6):
    echo "a equals 6";
    echo "!!!";
else:
    echo "a is neither 5 nor 6";
endif;

   

a equals 5...

[!NOTE] Mixing syntaxes in the same control block is not supported.

[!WARNING] Any output (including whitespace) between a switch statement and the first case will result in a syntax error. For example, this is invalid:

<?php
$foo = 1;
switch ($foo): ?>
    <?php case 1: ?>
    Foo is 1
<?php endswitch; ?>

   

ENTITY

Parse error: syntax error, unexpected T_INLINE_HTML "    ", expecting "endswitch" or "case" or "default" in script on line 4

Whereas this is valid, as the trailing newline after the switch statement is considered part of the closing ?ENTITY and hence nothing is output between the switch and case:

<?php
$foo = 1;
switch ($foo): ?>
<?php case 1: ?>
    Foo is 1
<?php endswitch; ?>

   

ENTITY

    Foo is 1

See also while, for, and if for further examples.