<?php
require_once 'Zend/Validate/EmailAddress.php';
function c_email($email)
{
  $validator = new Zend_Validate_EmailAddress();
  if($validator->isValid($email)){
    echo "輸入的E-mail地址：";
    echo $email."有效！<p>";
  }else{
    echo "輸入的E-mail地址：";
    echo $email."無效！";
    echo "失敗消息為：<p>";
    foreach($validator->getMessages() as $message){
      echo $message."<p>";
    }
    foreach($validator->getErrors() as $error){
      echo $error."<p>";
    }
  }
}
$e_m1 = "abc@123.com";
$e_m2 = "abc#123.com";
c_email($e_m1);
c_email($e_m2);

public function isValid($value)
{
    if (!is_string($value)) {
      $this->_error(self::INVALID);
      return false;
    }
    $matches = array();
    $length = true;
    $this->_setValue($value);
    // Split email address up and disallow '..'
    if ((strpos($value, '..') !== false) or
      (!preg_match('/^(.+)@([^@]+)$/', $value, $matches))) {
      $this->_error(self::INVALID_FORMAT);
      return false;
    }
    $this->_localPart = $matches[1];
    $this->_hostname = $matches[2];
    if ((strlen($this->_localPart) > 64) || (strlen($this->_hostname) > 255)) {
      $length = false;
      $this->_error(self::LENGTH_EXCEEDED);
    }
    // Match hostname part
    if ($this->_options['domain']) {
      $hostname = $this->_validateHostnamePart();
    }
    $local = $this->_validateLocalPart();
    // If both parts valid, return true
    if ($local && $length) {
      if (($this->_options['domain'] && $hostname) || !$this->_options['domain']) {
        return true;
      }
    }
    return false;
}