本文实例讲述了PHP正则验证Email的方法。分享给大家供大家参考。具体如下：
<?php
function validateEmail($email)
{
$isValid = true;
$atIndex = strrpos($email, "@");
if (is_bool($atIndex) && !$atIndex)
{
$isValid = false;
}
else
{
$domain = substr($email, $atIndex+1);
$local = substr($email, 0, $atIndex);
$localLen = strlen($local);
$domainLen = strlen($domain);
if ($localLen < 1 || $localLen > 64)
{
// local part length exceeded
$isValid = false;
}
else if ($domainLen < 1 || $domainLen > 255)
{
// domain part length exceeded
$isValid = false;
}
else if ($local[0] == '.' || $local[$localLen-1] == '.')
{
// local part starts or ends with '.'
$isValid = false;
}
else if (preg_match('/../', $local))
{
// local part has two consecutive dots
$isValid = false;
}
else if (!preg_match('/^[A-Za-z0-9-.]+$/', $domain))
{
// character not valid in domain part
$isValid = false;
}
else if (preg_match('/../', $domain))
{
// domain part has two consecutive dots
$isValid = false;
}
else if(!preg_match('/^(\.|[A-Za-z0-9!#%&`_=/$'*+?^{}|~.-])+$/', str_replace("\","",$local)))
{
// character not valid in local part unless
// local part is quoted
if (!preg_match('/^"(\"|[^"])+"$/', str_replace("\","",$local)))
{
$isValid = false;
}
}
if ($isValid && !(checkdnsrr($domain,"MX") || checkdnsrr($domain,"A")))
{
// domain not found in DNS
$isValid = false;
}
}
return $isValid;
}
?>
希望本文所述对大家的php程序设计有所帮助。
