append_form_file

Description:

public void append_form_file (string control_name, string filename, string content_type, Buffer body)

Adds a new MIME part containing body to this, using "Content-Disposition: form-data", as per the HTML forms specification.

this	a multipart (presumably of type "multipart/form-data")
control_name	the name of the control associated with this file
filename	the name of the file, or `null` if not known
content_type	the MIME type of the file, or `null` if not known
body	the file data