<s>
In	O
HTML	B-Language
,	O
a	O
file-select	O
control	O
is	O
a	O
component	O
of	O
a	O
web	B-General_Concept
form	I-General_Concept
with	O
which	O
a	O
user	O
can	O
select	O
a	O
local	O
file	O
.	O
</s>
<s>
When	O
the	O
form	O
is	O
submitted	O
(	O
perhaps	O
together	O
with	O
other	O
form	O
data	O
)	O
,	O
the	O
file	O
is	O
uploaded	O
to	O
the	O
web	B-Application
server	I-Application
.	O
</s>
<s>
There	O
,	O
when	O
the	O
file	O
arrives	O
,	O
some	O
action	O
usually	O
takes	O
place	O
,	O
such	O
as	O
saving	O
the	O
file	O
on	O
the	O
web	B-Application
server	I-Application
.	O
</s>
<s>
However	O
,	O
the	O
particular	O
action	O
that	O
takes	O
place	O
is	O
determined	O
by	O
the	O
server-side	B-Language
script	I-Language
to	O
which	O
the	O
form	O
is	O
submitted	O
.	O
</s>
<s>
Here	O
is	O
a	O
code	O
example	O
of	O
a	O
web	B-General_Concept
form	I-General_Concept
with	O
a	O
file-select	O
control	O
.	O
</s>
<s>
When	O
it	O
comes	O
to	O
the	O
rendering	O
on	O
the	O
screen	O
of	O
a	O
file-select	O
control	O
,	O
there	O
is	O
some	O
variation	O
among	O
web	B-Application
browsers	I-Application
.	O
</s>
<s>
Some	O
browsers	B-Application
,	O
notably	O
Firefox	B-Application
,	O
no	O
longer	O
allow	O
a	O
filename	O
to	O
be	O
typed	O
directly	O
in	O
.	O
</s>
<s>
The	O
mechanism	O
for	O
form-based	O
file	O
upload	O
was	O
originally	O
proposed	O
in	O
RFC	O
1867	O
(	O
published	O
November	O
1995	O
)	O
,	O
as	O
an	O
extension	O
to	O
HTML	B-Language
2.0	O
(	O
RFC	O
1866	O
)	O
,	O
after	O
its	O
publication	O
.	O
</s>
<s>
Form-based	O
file	O
upload	O
then	O
was	O
incorporated	O
in	O
HTML	B-Language
3.2	O
,	O
which	O
explicitly	O
refers	O
to	O
RFC	O
1867	O
for	O
further	O
information	O
on	O
form-based	O
file	O
upload	O
.	O
</s>
<s>
HTML	B-Language
4.01	I-Language
does	O
not	O
,	O
in	O
itself	O
,	O
describe	O
how	O
the	O
file-select	O
control	O
is	O
supposed	O
to	O
work	O
,	O
but	O
it	O
does	O
list	O
RFC	O
2388	O
and	O
RFC	O
1867	O
as	O
references	O
.	O
</s>
<s>
The	O
INPUT	O
element	O
is	O
used	O
to	O
create	O
a	O
file	B-General_Concept
select	I-General_Concept
control	O
.	O
</s>
<s>
It	O
has	O
been	O
noted	O
that	O
the	O
plural	O
"	O
files	O
"	O
in	O
the	O
above	O
quote	O
is	O
an	O
indication	O
that	O
,	O
in	O
HTML	B-Language
4.01	I-Language
,	O
a	O
single-file	O
select-control	O
still	O
was	O
supposed	O
to	O
handle	O
selection	O
of	O
multiple	O
files	O
and	O
not	O
just	O
a	O
single	O
file	O
.	O
</s>
<s>
This	O
would	O
enable	O
file-type	O
filtering	O
based	O
on	O
MIME	B-Application
type	I-Application
for	O
the	O
file-select	O
control	O
.	O
</s>
<s>
In	O
addition	O
,	O
it	O
is	O
proposed	O
that	O
the	O
INPUT	O
tag	O
have	O
an	O
ACCEPT	O
attribute	O
,	O
which	O
is	O
a	O
list	O
of	O
comma-separated	O
media	B-Application
types	I-Application
.	O
</s>
<s>
Basic	O
support	O
for	O
the	O
file-select	O
control	O
was	O
adopted	O
quickly	O
by	O
browser	B-Application
vendors	O
.	O
</s>
<s>
For	O
example	O
,	O
already	O
Internet	B-Application
Explorer	I-Application
4	O
,	O
Netscape	B-Protocol
Navigator	I-Protocol
2.0	O
and	O
Opera	B-Application
3.5	O
recognized	O
the	O
input	O
element	O
of	O
type	O
=	O
"	O
file	O
"	O
as	O
a	O
file-select	O
control	O
.	O
</s>
<s>
However	O
,	O
most	O
modern	O
browsers	B-Application
still	O
do	O
not	O
implement	O
the	O
file-select	O
control	O
as	O
it	O
was	O
intended	O
,	O
or	O
lack	O
certain	O
features	O
.	O
</s>
<s>
Form-based	O
upload	O
of	O
multiple	O
files	O
with	O
a	O
single	O
file-select	O
control	O
is	O
supported	O
in	O
current	O
versions	O
of	O
Chrome	O
,	O
Firefox	B-Application
,	O
Internet	B-Application
Explorer	I-Application
,	O
Safari	O
and	O
Opera	B-Application
.	O
</s>
<s>
One	O
source	O
states	O
that	O
Opera	B-Application
supports	O
multiple-file	O
selection	O
through	O
a	O
single	O
file-select	O
control	O
.	O
</s>
<s>
This	O
was	O
true	O
for	O
Opera	B-Application
versions	O
starting	O
from	O
3.5	O
,	O
in	O
which	O
the	O
file-upload	O
feature	O
was	O
introduced	O
.	O
</s>
<s>
However	O
,	O
with	O
the	O
first	O
beta	O
release	O
of	O
Opera	B-Application
7	O
,	O
this	O
function	O
was	O
no	O
longer	O
available	O
.	O
</s>
<s>
Firefox	B-Application
version	O
3.6	O
started	O
supporting	O
multiple-file	O
selection	O
,	O
allowing	O
the	O
developer	O
some	O
limited	O
access	O
to	O
the	O
files	O
themselves	O
prior	O
to	O
being	O
uploaded	O
to	O
the	O
server	O
,	O
via	O
the	O
HTML5	B-Language
File	I-Language
API	I-Language
.	O
</s>
<s>
This	O
feature	O
also	O
allows	O
users	O
to	O
drag-and-drop	O
files	O
from	O
external	O
applications	O
(	O
such	O
as	O
Windows	B-Protocol
Explorer	I-Protocol
)	O
directly	O
into	O
the	O
web	O
application	O
.	O
</s>
<s>
One	O
notable	O
example	O
of	O
support	O
for	O
this	O
feature	O
is	O
Gmail	B-Application
allowing	O
attachments	O
to	O
be	O
added	O
in	O
this	O
way	O
.	O
</s>
<s>
One	O
solution	O
is	O
to	O
use	O
client-side	O
scripting	O
such	O
as	O
JavaScript	B-Language
for	O
generating	O
an	O
extra	O
file-select	O
control	O
for	O
each	O
file	O
the	O
user	O
selects	O
for	O
upload	O
.	O
</s>
<s>
Using	O
CSS	B-Language
,	O
these	O
extra	O
file-select	O
controls	O
may	O
be	O
set	O
not	O
to	O
display	O
.	O
</s>
<s>
An	O
example	O
of	O
this	O
technique	O
is	O
demonstrated	O
in	O
the	O
for	O
jQuery	B-Language
.	O
</s>
<s>
Still	O
,	O
this	O
does	O
not	O
solve	O
the	O
problem	O
of	O
selecting	O
multiple	O
files	O
for	O
upload	O
in	O
Internet	B-Application
Explorer	I-Application
.	O
</s>
<s>
The	O
accept	O
attribute	O
is	O
currently	O
supported	O
by	O
Opera	B-Application
11+	O
,	O
Chrome	O
16+	O
,	O
Safari	O
6+	O
,	O
Firefox	B-Application
9+	O
and	O
Microsoft	B-Application
Internet	I-Application
Explorer	I-Application
10+	O
.	O
</s>
