我有这个函数在我的控制器下载文件，我存储在我的mongodb网格:
function download_presentation($ext,$store_filename)
{
$grid = $this->mongo->db->getGridFS();
//query the file object
$objects = $grid->find();
//set content-type header, output in browser
switch ($ext) {
case 'pdf':
$mimeType = 'Content-type: application/pdf';
break;
case 'jpg':
$mimeType = 'Content-type: image/jpg';
break;
case 'png':
$mimeType = 'Content-type: image/png';
break;
case 'doc':
$mimeType = 'Content-type: application/msword';
break;
case 'docx':
$mimeType = 'Content-type: application/vnd.openxmlformats-officedocument.wordprocessingml.document';
break;
case 'xls':
$mimeType = 'Content-type: application/vnd.ms-excel';
break;
case 'xlsx':
$mimeType = 'Content-type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
break;
case 'ppt':
$mimeType = 'Content-type: application/x-mspowerpoint';
break;
case 'pptx': $mimeType = 'Content-type: application/vnd.openxmlformats- officedocument.presentationml.presentation';
break;
default:
$mimeType='Content-type: application/pdf';
}
while($object = $objects->getNext()) :
if(($object->file['filename'])==$store_filename){
$content=$object->getBytes();
header("Content-Length: " . strlen($content));
header($mimeType);
echo ($content);}
endwhile;
}每当我下载。ppt文件，它说PowerPoint不能打开这个文件，因为它不是。ppt。对于pptx文件，当我下载后打开它时，当我点击从PowerPoint弹出的"修复"时，它正在工作。同样的事情也发生在。doc/MS-Word上。只有pdf文件可以正常运行。谁能告诉我出了什么问题?
嗯，经过一年的阅读，理解和实现PHP，我能够回答我自己的问题，我已经使用ob_clean()方法修复了错误，它像一个魅力，希望这有助于将来的人…
$content= $object->getBytes();
header("Content-Length: " . strlen($content));
header($mimeType);
ob_clean();
echo($content);