如何下载带位置选择选项的文件

Question

I am downloading file from server to local computer like this:

$file = ( "TestFile.txt" );     
header( "Content-Type: application/octet-stream" );
header( "Accept-Ranges: bytes" );
header( "Content-Length: " . filesize( $file ) );
header( "Content-Disposition: attachment; filename=testfile.txt" );
readfile( $file );

It is working but it always save file in download folder without asking location. I want to open window like saving any document in OpenOffice/MS Word with option to choose any location on file system and create new folder option. My desired window also opears when we save as in browser window.

Hope you understand my problem. Is it possible to do this which work in all browsers/OS.

Thanks

Answer 1

The specification of Content-Disposition reads that the receiving user agent should ignore any path component in filename parameter value:

The receiving [user agent] SHOULD NOT respect any directory path information that may seem to be present in the filename parameter. The filename should be treated as a terminal component only.

The reason for this is that it prones a security vulnerability:

Since this memo provides a way for the sender to suggest a filename, a receiving [user agent] must take care that the sender's suggested filename does not represent a hazard. Using UNIX as an example, some hazards would be:

• Creating startup files (e.g., ".login").
• Creating or overwriting system files (e.g., "/etc/passwd").
• Overwriting any existing file.
• Placing executable files into any command search path (e.g., "~/bin/more").
• Sending the file to a pipe (e.g., "| sh").