C++ DLL from VBA

[thekind78]

Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:

func(char[],int[],int)

The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA

I have been trying some combination of the following:

func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.

 

[Equiangular]

use long instead of integer in vba
long is signed 32 bit integer

 

[Equiangular]

One point to add
You should use ByVal for the first and second parameter

The following link is quite useful
http://support.microsoft.com/?scid=kb;en-us;106553&x=16&y=9

use long instead of integer in vba
long is signed 32 bit integer

Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:

func(char[],int[],int)

The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA

I have been trying some combination of the following:

func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.

 

[thekind78]

One point to add
You should use ByVal for the first and second parameter

The following link is quite usefulhttp://support.microsoft.com/?scid=kb%3Ben-us%3B106553&x=16&y=9

use long instead of integer in vba
long is signed 32 bit integer

Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:
func(char[],int[],int)
The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA
I have been trying some combination of the following:
func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.- Hide quoted text -

- Show quoted text -

Equiangular,
Thanks for your help. I'm still getting a Segmentation fault of sorts
as Excel just shuts down. Is it necessary to register the dll before
using it? Thank you.

 

[thekind78]

One point to add
You should use ByVal for the first and second parameter

The following link is quite usefulhttp://support.microsoft.com/?scid=kb%3Ben-us%3B106553&x=16&y=9

use long instead of integer in vba
long is signed 32 bit integer
thekind78 wrote:
Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:
func(char[],int[],int)
The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA
I have been trying some combination of the following:
func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.- Hide quoted text -

- Show quoted text -

Equiangular,
Thanks for your help. I'm still getting a Segmentation fault of sorts
as Excel just shuts down. Is it necessary to register the dll before
using it? Thank you.- Hide quoted text -

- Show quoted text -

Also,
Is it necessary for the DLL to include a LibMain function? It
contains a DllEntryPoint function. Thanks for your help.

 

[Equiangular]

Hi

I'm sorry that I'm not familiar with c++ DLL. For "traditional" DLL (I
mean not activeX DLL), there is no need to register. Just call in a
similar way like windows API.

Some correction to make, the second parameter should be byref as this is
an array.

One point to add
You should use ByVal for the first and second parameter
The following link is quite usefulhttp://support.microsoft.com/?scid=kb%3Ben-us%3B106553&x=16&y=9
Equiangular wrote:
use long instead of integer in vba
long is signed 32 bit integer
thekind78 wrote:
Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:
func(char[],int[],int)
The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA
I have been trying some combination of the following:
func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.- Hide quoted text -
- Show quoted text -

Equiangular,
Thanks for your help. I'm still getting a Segmentation fault of sorts
as Excel just shuts down. Is it necessary to register the dll before
using it? Thank you.- Hide quoted text -

- Show quoted text -

Also,
Is it necessary for the DLL to include a LibMain function? It
contains a DllEntryPoint function. Thanks for your help.

 

[Equiangular]

The following URL gives a step by step example

www.che.utexas.edu/cache/newsletters/spring2001_useofc.pdf

Hope it's useful to you

One point to add
You should use ByVal for the first and second parameter
The following link is quite usefulhttp://support.microsoft.com/?scid=kb%3Ben-us%3B106553&x=16&y=9
Equiangular wrote:
use long instead of integer in vba
long is signed 32 bit integer
thekind78 wrote:
Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:
func(char[],int[],int)
The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA
I have been trying some combination of the following:
func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.- Hide quoted text -
- Show quoted text -

Equiangular,
Thanks for your help. I'm still getting a Segmentation fault of sorts
as Excel just shuts down. Is it necessary to register the dll before
using it? Thank you.- Hide quoted text -

- Show quoted text -

Also,
Is it necessary for the DLL to include a LibMain function? It
contains a DllEntryPoint function. Thanks for your help.

 

[thekind78]

The following URL gives a step by step example

www.che.utexas.edu/cache/newsletters/spring2001_useofc.pdf

Hope it's useful to you

One point to add
You should use ByVal for the first and second parameter
The following link is quite usefulhttp://support.microsoft.com/?scid=kb%3Ben-us%3B106553&x=16&y=9
Equiangular wrote:
use long instead of integer in vba
long is signed 32 bit integer
thekind78 wrote:
Hello all,
Trying to call a C++ function from VBA. Function is declared as
following in C++:
func(char[],int[],int)
The function reads the char*, does some manipulations on the data
within it, and writes the results to the int*. There are two things I
see as problems:
1) the int values in C++ are greater than the max value permitted in
VBA
2) not sure how to pass the parameters to the dll from VBA
I have been trying some combination of the following:
func(ByRef string, ByRef int(1), ByVal int)
i.e. sending down the address of the string, the address of the
first element of the integer array and the value of an integer which
corresponds to the number of iterations that are required for some
processing done in the C++ code. Can anyone suggest how to address the
two problems above? As it stands now, the code completely shuts down
Excel without even a warning. Some illegal memory addressing I guess
but not sure how to get around it. Thanks in advance.- Hide quoted text -
- Show quoted text -
Equiangular,
Thanks for your help. I'm still getting a Segmentation fault of sorts
as Excel just shuts down. Is it necessary to register the dll before
using it? Thank you.- Hide quoted text -
- Show quoted text -

Also,
Is it necessary for the DLL to include a LibMain function? It
contains a DllEntryPoint function. Thanks for your help.- Hide quoted text -

- Show quoted text -

Equiangular,
Thanks for your help.