[RESOLVED] IsObject Function

[Lee.B]

Am currently cleaning up code in preparation for VB.Net Migration.

Am Adding Option Explicit to my VB6 code where missing and have come across a situation I need assistance in resolving.

Code:
If IsObject(SomeControl) then
Msgbox "Control Exists in this project"
else
Msgbox "Control does not exist in this project"
Endif

This code works properly to detect the existence of a control providing that I do not include Option Explicit in my code.

If I do use Option Explicit and SomeControl does not exist in project then I get Undefined Variable error on SomeControl.

How do I use IsObject to detect presence of object when OptionExplicit is ON?

Lee

[Hack]

Welcome to the forums.

There is a function in your project called IsObject, right?

It needs to have one parameter passed to it, and that is what that code is attempting to do. It is an example. Apparently someone just copy 'n pasted the example without changing it to suit the individual needs of the project.

My guess is that you probably don't need it anyway.

[Lee.B]

IsObject is a VB6 Function

If there is an object in the project IsObject(Objectname) wil return True.
If ObjectName does not exist, IsObject(ObjectName) will return false.

Exception is if Option Explicit is included in project code then ObjectName MUST be defined even though it may not exist.

Hence, source of my confusion.

Sample code is just to illustratete my point - not production code.

[MartinLiss]

You are misunderstanding how IsObject is supposed to be used. It is not meant to tell you if an object exists in your app because surely know if it does because you have the code in front of you. Instead it is used to tell if a Variant contains an object or not. In other words if you had a Variant called MyVar and a label and you did

MyVar = Label1
MsgBox IsObject(MyVar)

You would see "True" displayed, but if you did

MyVar = "test"
MsgBox IsObject(MyVar)

you would see "False".

[Lee.B]

Martin:
Guess I was using it wrong for past few years.

I have a lot of reusable code and functions in a 400,000 line project made up of 24 VBP's and 150 forms.

I've used the IsObject to determine if a particular function or subroutine should do something specific if it's being called from within a particular project.

So, now I'm faced with finding a method to determine which project I'm executing within. Will probably just store a global variable for Project Name.

Thanks for clarifying this

Lee

[MartinLiss]

Now that we've helped you, you can help us by marking the thread as resolved. If you have JavaScript enabled you can do that easily by pulling down the Thread Tools menu and selecting the Mark Thread Resolved item. Also if someone has been particularly helpful you have the ability to affect their forum "reputation" by rating their post. (No need to do it for me.) Only those ratings that you give after you have 20 posts will actually count, but in all cases the person you rate will see your rating and know that you appreciate their help.

[MartinLiss]

You could modify the called functions to look for a new passed parameter that would tell it who was calling it.