用PHP从数组和cookie写入信息到文本文件

我试图从数组和cookie(已放入变量，即$ useratsby)写入已与PHP创建的文本文件的信息。下面是我想在文本文件中写入的代码。我试过用fwrite()和file_put_contents来写它，但我总是得到一个服务器错误。我想知道有没有人知道我要怎么做这件事?

$emailmsg = "Order: " . foreach ($productarray as $book=>$info)
                    {if ($book > 0)
                    {echo $info . ", Quantity: " . $book . "<br><br>";}
        } . "// Price: " . $usergatsby*12.99 + $usercatcher*10.99 + $userwaves*8.99 + $userstranger*7.99 + $userulysses*18.99 + $userpride*6.99 + $usermockingbird*9.99 + $userroad*11.99;

$textFile = text.txt;
$fileHandle = fopen($textFile, 'w') or die('There was an error.');
fwrite($fileHandle, $emailmsg);
fclose($fileHandle);