如何让IE下载pdf文件而不是直接打开


<?phpheader("content-type: text/html;charset=utf-8");
echo '<a href="oo.php">点击下载</a>';
?>oo.php
$file_path='test.pdf';
$file_name='test.pdf';
$fp=fopen($file_path,"r");
$file_size=filesize($file_path);header("Content-type:application/octet-stream");
header("Accept-Ranges:bytes");
header("Accept-Length:$file_size");
header("Content-Disposition:attachment;filename=".$file_name);$buffer=1024;
$file_count=0;
while(!feof($fp) && ($file_size-$file_count>0)){
$file_data=fread($fp,$buffer);
$file_count+=$buffer;
echo $file_data;
}
fclose($fp);