/**
 * Email地址函数
 *
 * @param 
 * @arrange (512.笔记) jb51.cc
 **/
function check_email_address($email) {
  // First,we check that there's one @ symbol,and that the lengths are right
  if (!ereg("^[^@]{1,64}@[^@]{1,255}$",$email)) {
    // Email invalid because wrong number of characters in one section,or wrong number of @ symbols.
    return false;
  }
  // Split it into sections to make life easier
  $email_array = explode("@",$email);
  $local_array = explode(".",$email_array[0]);
  for ($i = 0; $i < sizeof($local_array); $i++) {
    if (!ereg("^(([A-Za-z0-9!#$%&'*+/=?^_`{|}~-][A-Za-z0-9!#$%&'*+/=?^_`{|}~\.-]{0,63})|(\"[^(\\|\")]{0,62}\"))$",$local_array[$i])) {
      return false;
    }
  }
  if (!ereg("^\[?[0-9\.]+\]?$",$email_array[1])) { // Check if domain is IP. If not,it should be valid domain name
    $domain_array = explode(".",$email_array[1]);
    if (sizeof($domain_array) < 2) {
      return false; // Not enough parts to domain
    }
    for ($i = 0; $i < sizeof($domain_array); $i++) {
      if (!ereg("^(([A-Za-z0-9][A-Za-z0-9-]{0,61}[A-Za-z0-9])|([A-Za-z0-9]+))$",$domain_array[$i])) {
        return false;
      }
    }
  }
  return true;
}


/***   代码来自编程之家 jb51.cc（jb51.cc）   ***/