PHP变量连接和文本文件换行

我的php变量如下

$boothsizetopges = "CHILDREN'S CLUB MARCH 2013
EHIBITING COLLECTION NAME: $company
BOOTH SIZE: $booth_size
"; 
$companyinfo = "
CONTACT INFORMATION
EXHIBITING COLLECTION NAME: $company
BOOTH NUMBER: $booth
CONTACT: $contact
BOOTH SIZE: $booth_size
CONTACT CELL: $contact_cell
CONTACT EMAIL: $email
STREET ADDRESS: $street
CITY, STATE, ZIP: $city ";
$message = $boothsizetopges . $companyinfo ;

和我写$message到。txt文件的代码是

$myFile = "exfiles/".str_replace(" ","-",$_POST['companyname'])."_".time().".txt";
$fh = fopen($myFile, 'w') or die("can't open file");
$stringData = $message;
fwrite($fh, $stringData);
fclose($fh);

这里我的问题是在。txt文件输出是打印在单行没有换行…但是在邮件中，每一行的数据都很好。

需要帮助…