module CGI::HtmlExtension

#
file_field("NAME" => "name", "SIZE" => 40)

#
file_field("name", 40, 100)

#
file_field("name", 40)

#
file_field("name")

See #multipart_form() for forms that include file uploads.

Alternatively, the attributes can be specified as a hash.

of the file's _name_, not of the file's _contents_.
+name+, +size+, and +maxlength+. +maxlength+ is the maximum length
The attributes of the element can be specified as three arguments,

Generate an File Upload Input element as a string.

def file_field(name = "", size = 20, maxlength = nil)
  attributes = if name.kind_of?(String)
                 { "TYPE" => "file", "NAME" => name,
                   "SIZE" => size.to_s }
               else
                 name["TYPE"] = "file"
                 name
               end
  attributes["MAXLENGTH"] = maxlength.to_s if maxlength
  input(attributes)
end