RE: [ cf-dev ] Session Variables

[Albert Popkov]

no problem.

 

 

when CF works with complex variables (structures, arrays etc) doing <cfset myStruct2=myStruct>

will only create a new reference to the same space in memory, not a totally new variable.

(so both variables will then reference to the same space in memory)

 

try this code to see that:

<cfset myStruct=StructNew()>
<cfset myStruct.test="something">
<cfdump var="#myStruct#">
<cfset myStruct2=myStruct>
<cfset myStruct2.test="something else">
<cfdump var="#myStruct#">

 

when you did <cfset session.formResult[....]=form>, your session variable actually referenced the space in memory

where cold fusion keeps FORM structure, so on the next submit, this space in memory was overwritten, as well as

your session variable content. To avoid this you need to copy (or, better to say, clone) the variable content using Duplicate function.

 

It is different for simple variables (strings, numeric, boolean etc) - that's why WDDX approach worked.

 

 

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From: Sam Westlake [mailto:[EMAIL PROTECTED]
Sent: 13 April 2004 16:21
To: [EMAIL PROTECTED]
Subject: RE: [ cf-dev ] Session Variables

That's fixed it !! - Thanks Albert.

 

So why does this work?

 

Sam

---

From: Albert Popkov [mailto:[EMAIL PROTECTED]
Sent: 13 April 2004 15:55
To: [EMAIL PROTECTED]
Subject: RE: [ cf-dev ] Session Variables

you can try

<cfset session.formResult["#FORM.type#"] = Duplicate(FORM)>

 

this will actually create a new variable (without duplicate it should only create a reference to the same structure,

which is changed when the next form is submitted).

 

StructCopy may also be useful. There were some bugs reported with both Duplicate and StructCopy - such as

some problems working with nested structures - the best is to check macromedia.com for fixes etc.

 

 

---

From: Sam Westlake [mailto:[EMAIL PROTECTED]
Sent: 13 April 2004 14:05
To: [EMAIL PROTECTED]
Subject: [ cf-dev ] Session Variables

I am trying to persist session variables from one page to the next.

 

This is the application.cfm file:

 

<cfapplication name="game001"
  clientmanagement="Yes"
  sessionmanagement="Yes"
  sessiontimeout="#CreateTimeSpan(0,0,10,0)#"
  applicationtimeout="#CreateTimeSpan(0,0,10,0)#">

This is a template that runs at the beginning of each page (six pages - one for each formResult structure) to instatiate empty structure objects in the session scope:

 

<cfif  isDefined("session.formResult") IS FALSE>

 

 <!--- lock the session variable to stop race conditions --->
 <cflock name="game#SESSION.SessionID#"
  type="exclusive"
  timeout="3">
  
  <!--- instantite empty structures for each section --->
  <cfset session.formResult = StructNew()>  
  <cfset session.formResult.planning = StructNew()>
  <cfset session.formResult.buying = StructNew()>
  <cfset session.formResult.preparing = StructNew()>
  <cfset session.formResult.marketing = StructNew()>
  <cfset session.formResult.tenants = StructNew()>
  <cfset session.formResult.selling = StructNew()>
  
 </cflock>
</cfif>

 

This is a template that runs after every form submission ("type" is a hidden field in the form and has a value of one of the above structures, e.g., planning, buying, preparing, etc) - it copies the form results to the appropriate structure

 

<cfif isDefined("FORM.type")>
 <cfset session.formResult["#FORM.type#"] = FORM>
</cfif>

 

After running this last template then I cfdump the session scope. Each time it shows the form elements from the current form submission succesfully added to the appropriate structure in the session scope. But after submitting the next form then any form variables from the previous submission are not found - only the empty structure and the current variables each time

 

Anyone know why this is happening?

 

Thanks in advance,

 

Sam Westlake