Solved

Determine existing form fields?

Posted on 2003-11-18
6
684 Views
Last Modified: 2013-12-24
I've created a handy include template, PreserveForm.inc, that I use to generate hidden input fields populated the FORM object.  I use it to perpetually post form data to the next template, and the next, and so on, until I'm ready to update the database.

However, it doesn't work correctly if I duplicate existing fields.  If a form field is posted to an action page that then creates an input text field with the same name, the value gets appended with a preceding comma.

I get around this by creating a list of fieldnames in the variable PreserveExclude.

Here's how you call it:
<cfset PreserveExclude = "FIELD1,FIELD2,FIELD3">
<cfinclude template="PreserveForm.inc">

And here's the include file:

<!--- PreserveForm.inc:
Generate hidden form fields from existing form object.  Must be included just
before the end </form> tag after all input fields.
--->

<cfoutput>

<cfif IsDefined("form.fieldnames")>
      <cfloop list="#form.fieldnames#" index="f">
            <cfif NOT IsDefined("PreserveExclude")
                  OR ListFindNoCase(PreserveExclude, f) IS 0>
                  <cfset FEval = "ListLast(form." & f & ")">
                  <input name="#f#" type="Hidden" value="#Evaluate(FEval)#">
            </cfif>
      </cfloop>
</cfif>

</cfoutput>

So, it only creates hidden fields that are not in the PreserveExclude list.  I'd like to get rid of PreserveExclude.

Determining existing form fields in JavaScript is simple, just make sure they're created before looking for them.  But that's client side.

But in ColdFusion, let's say you have a complicated series of conditional include files that create <INPUT> fields.  You cannot be sure which fields were created.

So, the question is: Is there a way in ColdFusion to determine which form fields already exist?

Thanks in advance!
0
Comment
Question by:CarlsonCo
  • 2
6 Comments
 
LVL 19

Accepted Solution

by:
cheekycj earned 25 total points
ID: 9772815
I think the way you are doing it is the only way.  Remember CF is executed on the server side before your HTML form is rendered.  So CF doesn't know what the elements/fields of your form are.  JavaScript executes client side so it can easily find out.

Probably not what you wanted to hear but unfortunately a shortcoming of Serverside scripting.

CJ
0
 
LVL 11

Assisted Solution

by:hart
hart earned 25 total points
ID: 9776418
just a suggestion if u r forming hidden fields

then why not give the name as hidden_fielname.

this will differentiate it from the other normal fields and ur purpose will be solved.

Regards
Hart
0
 

Author Comment

by:CarlsonCo
ID: 9779168
That would mean rewriting all form and action pages throughout the system to be aware of the existance of hidden_fieldname.  I'm trying to avoid that.
0
 
LVL 11

Expert Comment

by:hart
ID: 9784764
then i don't think u can change what u r doing right now..

Regards
Hart
0

Featured Post

PRTG Network Monitor: Intuitive Network Monitoring

Network Monitoring is essential to ensure that computer systems and network devices are running. Use PRTG to monitor LANs, servers, websites, applications and devices, bandwidth, virtual environments, remote systems, IoT, and many more. PRTG is easy to set up & use.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

If you don't have the right permissions set for your WordPress location in IIS, you won't be able to perform automatic updates. Here's how to fix the problem.
Meet the world's only “Transparent Cloud™” from Superb Internet Corporation. Now, you can experience firsthand a cloud platform that consistently outperforms Amazon Web Services (AWS), IBM’s Softlayer, and Microsoft’s Azure when it comes to CPU and …
Established in 1997, Technology Architects has become one of the most reputable technology solutions companies in the country. TA have been providing businesses with cost effective state-of-the-art solutions and unparalleled service that is designed…

821 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question