Question

I have an external function like this:

extern "C" __declspec(dllexport) int __cdecl Identify(BSTR* bstrTemplates, __int64 lCount, __int64* lIndex, __int64* lRetCode) 

The bstrTemplates should be a string array.

How should my function look like in D7, and how to pass a string array to the external function. Can’t get my head around right now.

Answer 1

Finally solved the problem. It was the dynamic array. Looks like it can’t be used as C-style array. Looks like the length prefix confused the c dll. For the records here the prototype and usage:

Type

type
  TArrayOfWideString= array[0..999] of WideString;

Declaration

function Identify(var ATemplates: TArrayOfWideString; ATemplatesCount: int64; var ATemplateIndex: int64; var ARetCode: int64): Integer; cdecl; external 'Identify.dll';

Usage

var
  templateIndex, retCode: int64;
  templates: TArrayOfWideString;
  retval: integer;

//TODO: range checking for TArrayOfWideString needed

templates[0] := 'template1';
templates[1] := 'template2';

retVal := Identify(templates, 2, scanIndex, retCode);