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";
}
The above example will output:
a is NOT greater than b
The else statement is only executed if the
if expression evaluated to
false, and if there were any
elseif expressions - only if they evaluated to
false as well (see elseif).
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.