Dynamically creating a CF Tag

Question

Greetings,
I would like to dynamically determine what attributes are
present in a ColdFusion tag. I have done the following to test the
theory:
<cfset inputAttr['name'] = "tControlName">
<cfset inputAttr.label = "Control Label">
<cfset inputAttr.value = "Some string value">
<cfset inputAttr.type = "text">
<cfform name="fTest" method="post" action="">
<cfset tagAttr = "<cfinput ">
<cfloop collection=#inputAttr# item="attr">
<cfset tagAttr = '#tagAttr#
#attr#="#inputAttr[attr]#"'>
</cfloop>
<cfset tagAttr = "#tagAttr# >">
<cfoutput>#tagAttr#</cfoutput>
</cfform>
If I look at the source for the page it is correct, but no
input is creates. If however I change it to "<input" instead of
<cfinput" it works fine. Unfortunately I would like to use
attributes like validate that are only available in
<cfinput>.
I assume that the stuff within the <cfoutput> tags are
bding sent directly to the browser and bypassing the processing be
CF. So I have tried leaving out the "<cfinput " and ">" from
the tagAttr and using the following:
<cfinput "#tagAttr#" >
in a variety of forms but keep getting an error of one sort
or another.
Am I missing something or is this not possible?
Thanks for your help.

Answer 1

Hi Adam,
If I understand you correctly, you can do a similar sort of
thing in CF as
per what I touched on with <cfinvoke
argumentCollection="#stArgs#">. In
which the "real" argument is actually the collection, and the
other ones
are just "treated" as arguments as part of the compilation
process.
That is true.
In one of the previous CF betas I did lobby for this to be the
approach for
all CF tags. I'm not sure if it got addressed as an issue.
As some background, the reason why I lobbied for it was for
the exact
reason you have raised: <cfinput>, and doing pretty
much what you're trying
to do. I've since worked around it.
Exactly. So I wasn't so far off in what I wanted to do. From
the snippet I included you could see where I was going. Which is
something that you had tried to do as well. So had you said this, I
would have understood immediately you knew where I was going, that
you had been down that path and that it was a dead end. Mind you,
then I would not have meandered about for another couple of hours
learning interest things.
One thing you could look @ for these dynamic runtime forms is to
have a
gander @ the various CF frameworks out there. You'll probably
find the
work's already been done for you. And at the very least you
can dissect
the code and see how they've done it.
Will do.
Glad you actually seem to WANT to learn. A lot of
people here don't seem to.
Too true.
Yes. I'm reading a book that is like that (in peripheral places)
at
present. And there is a lot of shite code out there. Then
again... look
at your own old code. You probably see a lot of shite there
too. I
certainly do when I look @ MY old code (and, cough, some of
my new code
too!).
Too true. Yes my early code was not as good as today. But the
tools were not as good as today. (Not that there aren't problems
with the tools today. Some have just too much useless stuff that is
overkill. Who can learn the 10,000 classes available in .NET?) And
I always look at the code i've written, and not where it wasn't
very good and how it could have been done better. And then I apply
it to the next project.
Then too, I have written some strange code that works and
saves time, but was kluged to get around short comings in the
language. (That language now allows me to do what I wanted without
the work arounds.)
Good thinking. And hence you have situations as per this thread
in which
Ian asked what you were actually trying to achieve, as
perhaps what you
were asking was not the best question.
Pretty much. It more sends it to "STDOUT", if I can borrow
and absuse a
*nix term... in this case STDOUT generally being the HTTP
response, which
finds its way back to a client browser. But that's just *in
general*: the
data that CF generates does not need to be text, let alone
HTML, and it
does not have to be send to the HTTP response. Indeed it
doesn't have to
generate ANYTHING.
Agreed. Pardon me for being less than precise.
Ian touched on the notion of writing your CFML code to a string
and then
writing it to a file. There's not response or browser or HTML
involved in
that.
But it is not elegant and maybe not efficient. Unless one
writes out the whole form to one file and then loads it. Hmmm. But
not really a good answer I think.
Well I do have a tendency to call a spade a f***ing spade. And
then -
sometimes - proceed to hit the person I'm talking to with
it.
That's a good description. And I have been there too. But I
got away from it, and try to make comments in a positive way. Which
has its own problems.
Blimin' heck. I hope you're not accusing me of being Australian.
That's
not on at all.
Never! I had intended to include NZ, but it dropped out of my
mind. At least I didn't think you were English. (My wife is.) NZ is
nice. I have visited Christchurch and Marlborough. And a very brief
time in Nelson (I think. I drove from Marlborough to Nelson and
flew to Auckland and then back to States.)
Okay. So in the future you can reply to my posts. And I will
keep it in mind that you are a Kiwi and filter things
appropriately.