插入Blob - PHPMySQL文件后出现文件类型错误

我做了一个简单的脚本插入文件BLOB (mediumblob)在MySQL数据库。脚本工作正常，文件被上传并保存到表中，但当我下载文件并尝试打开它时，它说:"File type HTML document (text/html) is not supported"!

这意味着在保存文件类型时出现错误!

这是我的代码，请告诉我什么可能是错误的:

upload.php:

if (isset($_POST['upload'])) 
{
if(isset($_POST['upload']) && $_FILES['userfile']['size'] > 0)
{
$fileName = $_FILES['userfile']['name'];
$tmpName  = $_FILES['userfile']['tmp_name'];
$fileSize = $_FILES['userfile']['size'];
$fileType = $_FILES['userfile']['type'];
$fp      = fopen($tmpName, 'r');
$content = fread($fp, filesize($tmpName));
$content = addslashes($content);
fclose($fp);
if(!get_magic_quotes_gpc())
{
    $fileName = addslashes($fileName);
}
$p = $cnx->prepare('INSERT INTO commandes (name, size, type, content) VALUES(:name, :size, :type, :content)');
$p->execute(array('name'=>$fileName, 'size'=>$fileSize, 'type'=>$fileType, 'content'=>$content));    
echo "<br>File $fileName uploaded<br>";
}
}

Download.php:

$p = $cnx->prepare('SELECT cmd_id, name FROM commandes');
$p->setFetchMode(PDO::FETCH_OBJ);
$p->execute();
if($p->rowCount() == 0)
{
echo "0 Element <br />";
}
else
{
while($data = $p->fetch())
{
?>
<a href="./downloadpdf.php?id=<?php echo $data->cmd_id;?>"><?php echo $data->name;?></a> <br>
<?php
}
}
if(isset($_GET['id']))
{
$id = $_GET['id'];
$q = $cnx->prepare('SELECT * FROM commandes WHERE cmd_id = :cmd_id');
$q->setFetchMode(PDO::FETCH_OBJ);
$q->execute(array('cmd_id'=>$id));
while($getFile = $q->fetch())
{
header("Content-length: $getFile->size");
header("Content-type: $getFile->type");
header("Content-Disposition: download; filename=$getFile->name");
echo $getFile->pdf;
exit;
}
}

谢谢!