else

Often you'd want to execute a statement if a certain condition is met, and a different statement if the condition is not met. This is what else is for. else extends an if statement to execute a statement in case the expression in the if statement evaluates to false. For example, the following code would display a is greater than b if $a is greater than $b, and a is NOT greater than b otherwise:

<?php
$a = 3;
$b = 5;
if ($a > $b) {
  echo "a is greater than b\n";
} else {
  echo "a is NOT greater than b\n";
}

a is NOT greater than b

Note: Dangling else

In case of nested if-else statements, an else is always associated with the nearest if.

<?php
$a = false;
$b = true;
if ($a)
    if ($b)
        echo "b";
else
    echo "c";

The above example will output:

Despite the indentation (which does not matter for PHP), the else is associated with the if ($b), so the example does not produce any output. While relying on this behavior is valid, it is recommended to avoid it by using curly braces to resolve potential ambiguities.