if (!ereg('^[0-9][0-9]-[0-9][0-9]-[0-9][0-9][0-9][0-9]$', $date)){
//I got an error when I used "[0-9]{2}" instead of "[0-9][0-9]"
//^ matches start of string and $ matches end.
  &errors_present = TRUE;
  $errors .= "date not valid";
}
if (!ereg('^[a-zA-Z ]+$', $date)){
//etc.

preg_match("/^[0-9]{2}-[0-9]{2}-[0-9]{4}$/",$date)

function is_date($value) {
  // If the value of the field is empty, immediately return false.
  if (empty($value)) { return FALSE; }
 
  // Attach the exploded values to variables.
  list($day, $month, $year) = explode("/", $value);
 
  // Check those variables in the checkdate function. If it's valid, the function returns true.
  return checkdate($month, $day, $year);
}

preg_match("/^[0-9]{4} - [0-9]{4}$/", $time)

$time = "0900 - 1730";
 
// If there is one occurence of the needle in the value, then explode the array.
// If there is not, set it to an empty array.
if (substr_count($time, " - ") == 1) {
  list($startTime, $endTime) = explode(" - ", $time);
} else {
  list($startTime, $endTime) = array(0, 0);
}

$name = O'Reilly
 
$sanitisedName = mysql_real_escape_string($name);