Hi

in the few lines of code below which was from Dave Petersen and Joe U, the
use of the Excel command ForceFullCalculation does not produce a standard
compilation error (due to late binding apparently), whereas it would if it
was just
Thisworkbook.ForceFullCalculation

If Val(Application.Version) > 11 Then
Set oWkBk = ThisWorkbook
oWkBk.ForceFullCalculation = True
Debug.Print "Running forced calculation"
End If

Can someone explain briefly WHY late binding applies in this area?

Many thanks

Tim

Just my thoughts -- could be completely wrong technically. But it satisfies my
curiosity <vbg>.

Excel knows all the properties and methods for ThisWorkbook just like it knows
all the properties and methods for a Range object.

But it has no idea what you're doing with a variable declared as an Object.

So no matter what version you're using if you use ThisWorkbook, excel knows --
you can't fool it.

But if you use the Object variable, excel doesn't know or care until the code
actually runs.

On 12/16/2011 05:02, Tim Childs wrote:
> Hi
>
> in the few lines of code below which was from Dave Petersen and Joe U, the use
> of the Excel command ForceFullCalculation does not produce a standard
> compilation error (due to late binding apparently), whereas it would if it was just
> Thisworkbook.ForceFullCalculation
>
> If Val(Application.Version) > 11 Then
> Set oWkBk = ThisWorkbook
> oWkBk.ForceFullCalculation = True
> Debug.Print "Running forced calculation"
> End If
>
> Can someone explain briefly WHY late binding applies in this area?
>
> Many thanks
>
> Tim

--
Dave Peterson

On 16/12/2011 11:02, Tim Childs wrote:
> Hi
>
> in the few lines of code below which was from Dave Petersen and Joe U,
> the use of the Excel command ForceFullCalculation does not produce a
> standard compilation error (due to late binding apparently), whereas it
> would if it was just
> Thisworkbook.ForceFullCalculation
>
> If Val(Application.Version) > 11 Then
> Set oWkBk = ThisWorkbook
> oWkBk.ForceFullCalculation = True
> Debug.Print "Running forced calculation"
> End If
>
> Can someone explain briefly WHY late binding applies in this area?

Excel doesn't bother to check if the object oWkBk can execute the
statement "ForceFullCalculation = True" until it reaches that line.

Protected with this code you can insert completely invalid invocations
of non-existent and fictitious methods of oWkBk eg.

oWkBk.Zork Xyzzy = "Hello Sailor"

It will give a runtime error 438 "Object doesn't support property of
method" if you ever execute the line but not until. So it is quite a
clever way to hide Version related incompatibilities from the compiler.

I am pretty sure no versions of XL ever supported the Zork method.
(a prehistoric text based adventure game)

Regards,
Martin Brown

Hi Martin and Dave

MANY thanks for those responses - interesting to hear what the experts get
up to with overcoming version incompatibilities.

best wishes

Tim

("Qu: Upgrades - Progress isn't all what it's cracked up to be?").

"Martin Brown" <|||newspam|||@nezumi.demon.co.uk> wrote in message
news:jcfdh7$a8l$(E-Mail Removed)...
> On 16/12/2011 11:02, Tim Childs wrote:
>> Hi
>>
>> in the few lines of code below which was from Dave Petersen and Joe U,
>> the use of the Excel command ForceFullCalculation does not produce a
>> standard compilation error (due to late binding apparently), whereas it
>> would if it was just
>> Thisworkbook.ForceFullCalculation
>>
>> If Val(Application.Version) > 11 Then
>> Set oWkBk = ThisWorkbook
>> oWkBk.ForceFullCalculation = True
>> Debug.Print "Running forced calculation"
>> End If
>>
>> Can someone explain briefly WHY late binding applies in this area?
>
> Excel doesn't bother to check if the object oWkBk can execute the
> statement "ForceFullCalculation = True" until it reaches that line.
>
> Protected with this code you can insert completely invalid invocations of
> non-existent and fictitious methods of oWkBk eg.
>
> oWkBk.Zork Xyzzy = "Hello Sailor"
>
> It will give a runtime error 438 "Object doesn't support property of
> method" if you ever execute the line but not until. So it is quite a
> clever way to hide Version related incompatibilities from the compiler.
>
> I am pretty sure no versions of XL ever supported the Zork method.
> (a prehistoric text based adventure game)
>
> Regards,
> Martin Brown