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Use a specific DLL developed in C in a Delphi application

I got a DLL developed by somebody else (see attachment) in C and I want to use it in my Delphi 2009 application
I specifically want to call the routine CalcDDTable
I think I have no (?) difficulty to define the routine in my application
Now this routine uses arrays
One passed as input and the other containing the result
The input one contains unsigned integers
Does that exists in Delphi ?
DLL-dds-21-k.pdf

ASKER CERTIFIED SOLUTION

Ephraim Wangoya

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Ephraim Wangoya

Do you still need more help with this or was it only the datatype mapping that you needed?

LeTay

ASKER

The datatype was my first question
I will now try using the DLL and may ask for additional stuff in the coming hours/days

MerijnB

Do you happen to have a .h file of the dll?

LeTay

ASKER

Yes, I have everything but a .h file can't help in Delphi, can it ?

LeTay

ASKER

Based on what I could understand from the documentation, I put the DDS.DLL in my executable directory and coded this in the Unit that uses it :
unit UDDS;

interface

function CalcDDtable(ddTableDeal:array of Cardinal;var ddTableResults:array of integer):integer; stdcall; external 'DDS.DLL';
procedure DDSolver;

implementation

procedure DDSolver;
var
ddTableDeal:array[1..16] of Cardinal;
ddTableResults:array[1..20] of integer;
begin
.../... work to fill in ddTableDeal array
CalcDDtable(ddTableDeal,ddTableResults);
.../... work to get back results from ddTableResults
end;

Now I get a access violation in CalcDDtable execution on some address for read address some other address
Is the declaration of the function correct (stdcall, var for second argument) ?
And the real arguments passed ?

Thanks to help on this

LeTay

ASKER

Hello, I found my error
I did not declare argument via a structure (TRec)
Now I did and it works perfectly well

LeTay

ASKER

Many thanks
I did not realise that interfacing with external DLL written in C was so easy, finally !