CFSaveContent And THISTAG.GeneratedContent Tip

Posted February 18, 2008 at 7:27 AM by Ben Nadel

Tags: ColdFusion

Over the weekend, when I was working on my Dig Deep Fitness prototype, I thought of a neat little trick. I am sure that this has been done by many people, but it had never occurred to me. I was working with a ColdFusion custom tag in which I needed to replace the generated content of the tag. Normally, when I would do something of this nature, I would simply store the new content in a CFSaveContent tag buffer and then set that variable into the THISTAG.GeneratedContent variable:

  • <!---
  • We only want to execute this after the tag has
  • executed. That way, we will know all the child
  • tags and content that has been generated.
  • --->
  • <cfif (THISTAG.ExecutionMode EQ "End")>
  •  
  • <!--- Create the new tag content. --->
  • <cfsavecontent variable="VARIABLES.NewContent">
  • <cfoutput>
  •  
  • <!---
  • Put the new content in here that you want the
  • ColdFusion custom custom to actually produce.
  • --->
  •  
  • </cfoutput>
  • </cfsavecontent>
  •  
  •  
  • <!--- Set the tag's new content. --->
  • <cfset THISTAG.GeneratedContent = VARIABLES.NewContent />
  •  
  • </cfif>

But this weekend, as I was writing a tag like that, it hit me! Why not just store the CFSaveContent buffer directly into the GeneratedContent of the tag? Why bother even going through an intermediary variable:

  • <!---
  • We only want to execute this after the tag has
  • executed. That way, we will know all the child
  • tags and content that has been generated.
  • --->
  • <cfif (THISTAG.ExecutionMode EQ "End")>
  •  
  • <!--- Reset the tag content. --->
  • <cfsavecontent variable="THISTAG.GeneratedContent">
  • <cfoutput>
  •  
  • <!---
  • Put any content in here that you want the
  • ColdFusion custom custom to actually
  • produce. By storing the content diretly into
  • the GeneratedContent, it will set the output
  • that is displayed.
  • --->
  •  
  • </cfoutput>
  • </cfsavecontent>
  •  
  • </cfif>

Notice that the CFSaveContent tag is now storing its buffer directly into the THISTAG.GeneratedContent variable, which will, thereby, replace the content of the ColdFusion tag.

So, like I said, this is a really minor tip, but I think it has a big logical and visual impact on the layout of the ColdFusion custom tag. Thought I would share this with anyone who hadn't realized this shortcut yet.



Reader Comments

Michael Sharman
Feb 19, 2008 at 2:14 AM // reply »
17 Comments
10 Points

Another good tip Ben, thanks


phpnuke
Feb 26, 2008 at 9:17 PM // reply »
1 Comments
1 Points

It will come in handy. Go Ben go. :)


Ralph
Mar 17, 2011 at 2:12 PM // reply »
2 Comments
22 Points

Apparently, you cannot change THISTAG.GeneratedContent when THISTAG.ExecutionMode EQ "start"


Ben Nadel
Mar 17, 2011 at 2:26 PM // reply »
11,238 Comments
75,337 Points

@Ralph,

Correct - there is no generated content at that point since the body of the tag has not yet executed.


Orville Chomer
Apr 24, 2012 at 12:33 PM // reply »
4 Comments
45 Points

How come when I try to use ThisTag.generatedContent it does not seem to want to work?

I have a tag called <sample1>..

Here is a test using it:

  • <cf_sample1>This is a Test</cf_sample1>

Here is the contents of the tag file:

  • <cfif (thistag.executionMode eq "end")>
  • <cfoutput><br>value=#thistag.generatedContent#</cfoutput>
  • </cfif>

I get value=
but no value at all!


Orville Chomer
Apr 24, 2012 at 3:07 PM // reply »
4 Comments
45 Points

@Orville,

Found my own problem!

In my Application.cfm file I am using:

  • <cfsetting enablecfoutputonly="Yes">

So, in order for my custom tag to work as I would expect, I have to call it like so:

  • <cf_sample1><cfoutput>This is a Test</cfoutput></cf_sample1>

Then it works just fine!


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