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Peter T Peter T is offline
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Default Nothing Keyword Destories Objects rather than just resetting the variable to an empty variable

"Ronald R. Dodge, Jr." wrote in message
Where does it state this pointer bit within the documentations? All I see
in the documentations are by references for ByRef and a copy of the
variable with ByVal looking at different places.


Without searching I have no idea. Let me throw the question back at you -
where is something like the following documented:

" ByVal - Creates a whole new replica of the object with all of the same
settings as the object that is being passed onto it"

I'd be surprised if you find that anywhere.

Also, how is it that I know it will work out the same way with my custom
objects similar to how things works out with the objects built into the
application itself such as Worksheet object as the Worksheet object is
directly tied to the WorkSheets collection object?


I don't know anything about your custom obects but I would have thought you
are best placed to demonstrate for yourself.

Maybe the following will demonstrate that ByVal and ByRef work with the same
intrinsic object, and that in the case of ByVal merely a new pointer to the
same object is created.

Sub test4()
Dim c As Class1

Set c = New Class1
proc c, c

MsgBox c.x & vbCr & c.y & vbCr & ObjPtr(c) ' all same
End Sub

Sub proc(ByRef cr As Class1, ByVal cv As Class1)

cr.x = ObjPtr(cr)
cv.y = ObjPtr(cv)

Set cv = New Class1
cv.y = 123
MsgBox cv.y

End Sub

'' in class1
Public x As Long, y As Long

Regards,
Peter T


"Peter T" <peter_t@discussions wrote in message
...
ByVal - Creates a whole new replica of the object with all of the same
settings as the object that is being passed onto it


No it doesn't. It creates a new (temporary) pointer to the original
intrinsic object.

As far as the original object's properties are concerned there is no
difference between using ByRef and ByVal.

Regards,
Peter T


"Ronald R. Dodge, Jr." wrote in message
...
The way I understood the ByRef and ByVal are the following:

ByRef - References to the object, and any changes done to the object is
done for any variable referencing to that object, rather it be done in
the original code or in the code referencing to the object.

ByVal - Creates a whole new replica of the object with all of the same
settings as the object that is being passed onto it, but any changes
done to the original object is not reflects in the new object, just like
any changes done in the new object is not reflected in the original
object.

Though I haven't fully tested it to be sure with object variables, but
simple data type variables does work like this.

--
Thanks,

Ronald R. Dodge, Jr.
Production Statistician
Master MOUS 2000
"Peter T" <peter_t@discussions wrote in message
...
Afraid I don't follow most of that, maybe a simple example might help.

One thing though, I think you are misunderstanding the difference of
passing an object byref & byval. Either way, any changes to the
object's properties will persist.

The only difference is with byval a new pointer to the original object
is created and passed. This means even if you destroy or reassign the
byval object within the procedure, the original object variable will
continue point to the same object.

Regards,
Peter T



"Ronald R. Dodge, Jr." wrote in message
...
Office XP, SP3 (VBA 6.0)
WIN XP, SP2


I have read over the text dealing with custom objects

According to the text that I have read online from MS themselves, the
keyword "NOTHING" should only destroy the object when there is no
other variable refering to that object. However, as I have learned
the hard way, that is not the case. Any time any variable is set to
NOTHING, the object is destroyed, so any object variable referencing
to that object is then also set to NOTHING.

Example:

PayCode collection has a set of objects containing properties. One of
those PayCode objects is passed onto an Employee Object. It's passed
into the employee object via a property with the object using the
ByRef within the signature line, so if there's any changes to the
PayCode object, it's not only changed within the PayCodes collection,
but also within the Employee's PayCode reference to it.

However, if the Employee Object is set to be destroyed, via the clean
up code, the code should be to set the object variable within the
Employee Object to NOTHING. However, doing that not only does that,
but also set's that particular object within the PayCodes collection
to NOTHING as if the object itself has been destroyed.

How do I resolve this issue, so as I can have it reset only the
variable, not destroy the actual object, but yet, also allow for
changes to carry into the variable when they are done into the main
object?

--
Thanks,

Ronald R. Dodge, Jr.
Production Statistician
Master MOUS 2000