com, Function-Pointer?

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com >> Function-Pointer?

by Christoph Basedau » Wed, 24 Aug 2005 04:11:59 GMT

Hi

I have an ActiveX-DLL for validating user-entries from UI-Controls (mostly text-boxes)
The validation-method is very basic.
It validates whether the data entered matches the expected datatype (int, long, double etc)
and optionally minimae and maximae for numeric and date values or length
and pattern for strings.
In order to make a more specific validation i would like to pass a function-pointer
from the client to the the dll, that points to a boolean validation function.
In JavaScript one can pass a func-pointer by simply passing its name (without brackets),
in C/C++ it is similar.
Is there such a thing in VB (Maybe AdressOf, or CallByName)?

Any help appreciated.

--
Gruesse, Christoph


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com >> Function-Pointer?

by Karl E. Peterson » Wed, 24 Aug 2005 04:24:02 GMT





Yes, AddressOf will work fine, if you're passing the function pointer directly, as a
parameter to the DLL call. If you need to stuff the pointer into a structure, you
can do so something like this:

wincls.lpfnWndProc = FcnPtr(AddressOf WindowProc)

Private Function FcnPtr(ByVal Whatever As Long) As Long
' Return whatever was passed.
FcnPtr = Whatever
End Function

--
Working Without a .NET?
http://classicvb.org/petition




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com >> Function-Pointer?

by scott.marquardt » Thu, 01 Sep 2005 02:00:00 GMT

Pinging Chris --

Some time ago you posted a superb script for walking Internet
Explorer's history.

Simple question: is it possible to retreive more granular date/time
information, or is it stored only to minute precision?

Sorry to interrupt, gentlemen . . .

- Scott


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Function-Pointer?

by Christoph Basedau » Thu, 01 Sep 2005 18:03:07 GMT

Karl E. Peterson schrieb:





Thanks Karl

AdressOf does the trick. Thanks very much.


If you need to stuff the pointer into a

--
Gruesse, Christoph


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Function-Pointer?

by Christoph Basedau » Thu, 01 Sep 2005 18:04:13 GMT

XXXX@XXXXX.COM schrieb:


Sorry i am afraid i can't remember of the details.
afair it deals with GetDetailsOf which in 2nd position receives
a column-param, that retrieves the specific information.
it's not doucmented which column returns what data, so you could simply
try your luck by looping over the first dozen of integers.

sth like

for i=0 to 20
WScript.Echo histFolder.GetDetailsOf (null, i), _
histFolder.GetDetailsOf (histItem, i)
next


where histFolder is the history folder as Shell Special Folder
and histItem is an ShellFolderItem.

--
Gruesse, Christoph


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Function-Pointer?

by scott.marquardt » Fri, 09 Sep 2005 13:08:07 GMT

Thanks. Yeah, no luck. Minute granularity it is, I'm afraid.


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