一．查看邮件是否已被阅读

当你发送邮件时，你肯定很想知道你的邮件是否已被对方查看。下面的代码就能实现记录阅读你邮件的IP地址，还有实际的阅读日期和时间。
复制代码 代码如下:
error_reporting(0);
Header("Content-Type: image/jpeg");
//Get IP
if (!empty($_SERVER['HTTP_CLIENT_IP']))
{
$ip=$_SERVER['HTTP_CLIENT_IP'];
}
elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR']))
{
$ip=$_SERVER['HTTP_X_FORWARDED_FOR'];
}
else
{
$ip=$_SERVER['REMOTE_ADDR'];
}
//Time
$actual_time = time();
$actual_day = date('Y.m.d', $actual_time);
$actual_day_chart = date('d/m/y', $actual_time);
$actual_hour = date('H:i:s', $actual_time);
//GET Browser
$browser = $_SERVER['HTTP_USER_AGENT'];

//LOG
$myFile = "log.txt";
$fh = fopen($myFile, 'a+');
$stringData = $actual_day . ' ' . $actual_hour . ' ' . $ip . ' ' . $browser . ' ' . "\r\n";
fwrite($fh, $stringData);
fclose($fh);
//Generate Image (Es. dimesion is 1x1)
$newimage = ImageCreate(1,1);
$grigio = ImageColorAllocate($newimage,255,255,255);
ImageJPEG($newimage);
ImageDestroy($newimage);
?>

源代码：http:///display-number-of-facebook-fans-in-full-text-on-your-wordpress-blog