How to write if x = a or x = b?

Question

PHP

if ( $x == $a or $x == $b )
if ( ($x == $a) or ($x == $b) )
if ( $x == ($a or $b) )

Answer 1

if ($x == $a || $x == $b)

Answer 2

switch ($x) {
  case $a:
  case $b:
    // делаем всякое
    break;
  default: // ничего не делаем
}

Answer 3

Just in case, I will draw your attention to the difference between "or" and "||": php.net/manual/en/language.operators.logical.php