php 发送带pdf附件的email 出现的是一长串字符串 请教怎么解决

php 发送带pdf附件的email 出现的是一长串字符串 请问如何解决
RT，发出的email附件不是一个pdf档，而变成了一长串字符串，

我的发送email的代码如下：

function mail($mailto, $userid, $data){
global $dsql,$cfg_adminemail,$cfg_webname,$cfg_basehost,$cfg_memberurl;
$mailtitle = $cfg_webname.":通知";
$file=fopen("D:/xampp/htdocs/pdftemp/dsfasdf.pdf","r");
$fileName=$data['oid'].'.pdf';
$mimeType ="application/pdf";
$boundary = "nextpart_".uniqid(""); //分隔符1
$boundary2 = "nextpart2_".uniqid(""); //分隔符2

//email头
$headers = "From: ".$cfg_adminemail."\r\nReply-To: $cfg_adminemail";
$headers .= "Content-type: multipart/mixed; boundary=\"$boundary1\"\r\n";

//读取文件
$read = fread($file, filesize("D:/xampp/htdocs/pdftemp/dsfasdf.pdf"));
//我们用base64方法把它编码
$read = base64_encode($read);
//把这个长字符串切成由每行76个字符组成的小块
$read = chunk_split($read);

//以下是mailbody正文
$mailbody = "--$boundary1----$boundary2
Content-type: text/plain;charset=iso-8859-1;
Content-transfer-encoding: 8bit";
$mailbody .= '致： '.$userid.',



This is mailbody--$boundary2--';

//以下是附件部分
$mailbody .="--$boundary1
Content-type: text/html; name=$fileName
Content-disposition: inline; filename=$fileName
Content-transfer-encoding: 8bit
$read
--$boundary1--";


$status = smail($mailto,$mailtitle,$mailbody,$headers);
setMail($mailto, $mailtitle, $mailbody, $headers, $status);
return $status;
}

// attachment

$body .= "--".$separator.$eol;

$body .= "Content-Type: application/octet-stream; name=\"".$filename."\"".$eol; 

$body .= "Content-Transfer-Encoding: base64".$eol;

$body .= "Content-Disposition: attachment".$eol.$eol;

$body .= $attachment.$eol;

$body .= "--".$separator."--";

$email = new PHPMailer();

$email->From      = 'you@example.com';

$email->FromName  = 'Your Name';

$email->Subject   = 'Message Subject';

$email->Body      = $bodytext;

$email->AddAddress( 'destinationaddress@example.com' );


$file_to_attach = 'PATH_OF_YOUR_FILE_HERE';


$email->AddAttachment( $file_to_attach , 'NameOfFile.pdf' );


return $email->Send();