Re: CFC required arguments
I usually want to know if the argument was passed, not if the argument
is the default value. With a default value, that value necessarily
has to be a legal value for the argument. Therefore there's no way to
tell if it was omitted or if the default value was explicitly passed.
Take this function for example:
...
The conditional will execute for both of these invocations:
test();
test("");
However, if I use this function:
...
The conditional will only execute for the former (where the argument
wasn't passed), and it'll treat "" just like it would treat any other
passed value.
cheers,
barneyb
On Wed, 1 Dec 2004 10:27:54 -0500, Sparrow-Hood, Walter
<[EMAIL PROTECTED]> wrote:
> Barney,
>I'm curious - why do you prefer structKeyExists() vs. setting
> default values?
>
> Walt
>
>
>
> -Original Message-
> From: Barney Boisvert [mailto:[EMAIL PROTECTED]
> Sent: Tuesday, November 30, 2004 6:26 PM
> To: CF-Talk
> Subject: Re: CFC required arguments
>
> If you use positional parameters, only parameters at the end can be
> left off. However, you can use named parameters without using
> CFINVOKE:
>
>
>
> I generally prefer to not specify a default for my option arguments,
> and then use structKeyExists() against the 'arguments' struct to check
> if they were passed. Since we don't have method overloading in CF,
> optional parameters (and their associated conditionals) are a
> necessary evil.
>
> cheers,
> barneyb
--
Barney Boisvert
[EMAIL PROTECTED]
360.319.6145
http://www.barneyb.com/blog/
~|
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RE: CFC required arguments
Barney, I'm curious - why do you prefer structKeyExists() vs. setting default values? Walt -Original Message- From: Barney Boisvert [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 30, 2004 6:26 PM To: CF-Talk Subject: Re: CFC required arguments If you use positional parameters, only parameters at the end can be left off. However, you can use named parameters without using CFINVOKE: I generally prefer to not specify a default for my option arguments, and then use structKeyExists() against the 'arguments' struct to check if they were passed. Since we don't have method overloading in CF, optional parameters (and their associated conditionals) are a necessary evil. cheers, barneyb On Wed, 1 Dec 2004 10:20:27 +1100, Paul Wilson <[EMAIL PROTECTED]> wrote: > I'm using createObject to invoke a CFC and one of the methods in the CFC > takes a number of arguments, all numeric but not all required. In the > CFC I have some conditional statements that do various things based on > the arguments passed in. > > do this > > Firstly is it a good idea to do this in a CFC? And secondly, how can I > pass is the only the arguments required .e.g. > > > The third argument is not required but this will throw an error. This > situation doesn't arise when you use cfinvoke as you can simply miss out > the cfinvokeargument tag. > > Thanks > -- Barney Boisvert [EMAIL PROTECTED] 360.319.6145 http://www.barneyb.com/blog/ ~| Special thanks to the CF Community Suite Gold Sponsor - CFHosting.net http://www.cfhosting.net Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185797 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
Re: CFC required arguments
On Wed, 1 Dec 2004 10:20:27 +1100, Paul Wilson <[EMAIL PROTECTED]> wrote: > do this If they are numeric arguments, you shouldn't have an empty string as the default. As other have hinted, specify required="false" but do not specify a default= value. Then you can test structKeyExists(arguments,'argname') to see whether the arg has actually been supplied. -- Sean A Corfield -- http://www.corfield.org/ Team Fusebox -- http://www.fusebox.org/ Breeze Me! -- http://www.corfield.org/breezeme Got Gmail? -- I have 1 invite "If you're not annoying somebody, you're not really alive." -- Margaret Atwood ~| Special thanks to the CF Community Suite Silver Sponsor - New Atlanta http://www.newatlanta.com Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185765 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
RE: CFC required arguments
Another option is to use the argumentCollection, i.e. obj.method( argumentCollection = structureContainingAllRequiredArguments ) Example: variables.argumentCollection = structNew(); variables.argumentCollection.argument1 = form.argument1; variables.argumentCollection.argument2 = url.argument2; variables.argumentCollection.argument3 = variables.argument3; obj.method( argumentCollection = variables.argumentCollection ) Off course if all arguments were in the form scope you could do obj.method( argumentCollection = form ) -- Taco Fleur Senior Web Systems Engineer http://www.webassociates.com -Original Message- From: Paul Wilson [mailto:[EMAIL PROTECTED] Sent: Wednesday, 1 December 2004 9:20 AM To: CF-Talk Subject: CFC required arguments I'm using createObject to invoke a CFC and one of the methods in the CFC takes a number of arguments, all numeric but not all required. In the CFC I have some conditional statements that do various things based on the arguments passed in. do this Firstly is it a good idea to do this in a CFC? And secondly, how can I pass is the only the arguments required .e.g. http://www.ruwebby.com Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185761 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
Re: CFC required arguments
Another alternative is to use named arguments. assuming your function is defined as: On Wed, 1 Dec 2004 10:20:27 +1100, Paul Wilson wrote: > > >>> >>The third argument is not required but this will throw an error. This >>situation doesn't arise when you use cfinvoke as you can simply miss out >>the cfinvokeargument tag. >> > > > Generally in the CFC, I list the required arguments first and then the > optional ones, primarily so I can use the obj.testmethod() syntax. > So, I'd suggest re-arranging the order of the arguments in your CFC. > This may require altering the calls to that method in other pages, of > course. > > Scott > -- Stephen Milligan Code poet for hire http://www.spike.org.uk Do you cfeclipse? http://cfeclipse.tigris.org ~| Special thanks to the CF Community Suite Gold Sponsor - CFHosting.net http://www.cfhosting.net Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185759 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=11502.10531.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
RE: CFC required arguments
By named parameters. Offcourse the argument name has to match the name in the method. > do this > Firstly is it a good idea to do this in a CFC? Not sure what to answer here, I know in OOP it's a bad thing to have switches and if's in a method. Maybe your better off creating another method? It's a shame we can't overload methods like in Java :-( -- Taco Fleur Senior Web Systems Engineer http://www.webassociates.com -Original Message- From: Paul Wilson [mailto:[EMAIL PROTECTED] Sent: Wednesday, 1 December 2004 9:20 AM To: CF-Talk Subject: CFC required arguments I'm using createObject to invoke a CFC and one of the methods in the CFC takes a number of arguments, all numeric but not all required. In the CFC I have some conditional statements that do various things based on the arguments passed in. do this Firstly is it a good idea to do this in a CFC? And secondly, how can I pass is the only the arguments required .e.g. http://www.newatlanta.com Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185757 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
Re: CFC required arguments
If you use positional parameters, only parameters at the end can be left off. However, you can use named parameters without using CFINVOKE: I generally prefer to not specify a default for my option arguments, and then use structKeyExists() against the 'arguments' struct to check if they were passed. Since we don't have method overloading in CF, optional parameters (and their associated conditionals) are a necessary evil. cheers, barneyb On Wed, 1 Dec 2004 10:20:27 +1100, Paul Wilson <[EMAIL PROTECTED]> wrote: > I'm using createObject to invoke a CFC and one of the methods in the CFC > takes a number of arguments, all numeric but not all required. In the > CFC I have some conditional statements that do various things based on > the arguments passed in. > > do this > > Firstly is it a good idea to do this in a CFC? And secondly, how can I > pass is the only the arguments required .e.g. > > > The third argument is not required but this will throw an error. This > situation doesn't arise when you use cfinvoke as you can simply miss out > the cfinvokeargument tag. > > Thanks > -- Barney Boisvert [EMAIL PROTECTED] 360.319.6145 http://www.barneyb.com/blog/ ~| Special thanks to the CF Community Suite Silver Sponsor - RUWebby http://www.ruwebby.com Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185755 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
Re: CFC required arguments
On Wed, 1 Dec 2004 10:20:27 +1100, Paul Wilson wrote: > > The third argument is not required but this will throw an error. This > situation doesn't arise when you use cfinvoke as you can simply miss out > the cfinvokeargument tag. > Generally in the CFC, I list the required arguments first and then the optional ones, primarily so I can use the obj.testmethod() syntax. So, I'd suggest re-arranging the order of the arguments in your CFC. This may require altering the calls to that method in other pages, of course. Scott -- - Scott Brady http://www.scottbrady.net/ ~| Special thanks to the CF Community Suite Silver Sponsor - RUWebby http://www.ruwebby.com Message: http://www.houseoffusion.com/lists.cfm/link=i:4:185754 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
