Problem with html "MAX_FILE_SIZE" for upload

[enterume]

Hi,

Actually I am trying to use the HTML:

<input type="hidden" name="MAX_FILE_SIZE" value="1000000" />

to detect the filesize before it is actually upload to server and checking in PHP, to save the server resource and speed up the checking before it reach server.

However, it seem like it will bypass or ignore the setting in the hidden field to control the file size of files to be uploaded.

Any idea?

[Weedpacket]

Remember that the field is only a hint to the client, and can never be relied on to actually work.

enterume wrote:

However, it seem like it will bypass or ignore the setting in the hidden field to control the file size of files to be uploaded.

Not at all clear to me what you mean by this. Are you saying that it's not working at all? Remember that MAX_FILE_SIZE must precede the file input field.

[enterume]

Hi Weedpacket,

Yes, nothing output from PHP after the submit if the filesize is too large.

Below is the HTML of form:

<form enctype="multipart/form-data" action="/testdate.php" method="post">
<input type="hidden" name="MAX_FILE_SIZE" value="50000">
<div><input name="userfile[]" type="file"></div>
<input type="submit" value="Submit">
</form>

Please advice.

Thanks

[Kudose]

Just as Weedpacket pointed out, you cannot rely on MAX_FILE_SIZE, you need to verify the file uploaded was less than MAX_FILE_SIZE using PHP, and proceed accordingly.

i.e.

if(filesize($_FILES['file']['tmp_name']) <= $_POST['MAX_FILE_SIZE']) // do stuff

[Kudose]

Also, your file HTML field should look like:

<input name="userfile" type="file" />

[enterume]

Yes, I understand about the control based on the max file size under php.ini.

Imagine user try to upload 2 MB to the system, which my apps only allow 500kb to be uploaded. (Correct me if I am wrong. ) To what I understand, PHP will upload the entire file to server as temp. THEN, only able to allow me to get the file information, right?

If YES, then I am seeking a way which allow me to check before the entire file being uploaded to my server, by using PHP, or other cgi/java? In order for me to save the resources and reduce the time for invalid upload checking.

Thank!

[Kudose]

I could be wrong, but I am fairly positive you will need to turn to Perl or Java to mess with the streaming data.

I say this because I know you can use Perl to make file upload percent bars, but PHP can't see the stream.