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Calling external DLL, How to declare and get values.

Posted on 2004-10-27
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Last Modified: 2010-04-05
Hello,

I have a DLL I wrote in PowerBasic where I have a function declared like this:

FUNCTION GetAllAdapters(Target2 AS ASCIIZ) EXPORT AS LONG (the long is a lpstr)

In my Delphi code I declared this function like this:

Function GETALLADAPTERS(Target2:lpstr): lpstr;  External 'newnic2.dll';

My question is how to set up the call with the string pointers and read the string from the pointer returned. I have tried a couple of different things, but I cannot narrow down the problem to my declare or the call.

Any help is appreciated.

Thanks
Kent
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Question by:KentDRuddick
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2 Comments
 
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Accepted Solution

by:
Lee_Nover earned 500 total points
ID: 12430356
instead of lpstr in delphi use PChar .. delphi should automatically handle type conversions to/from string/PChar
also set the calling convention to stdcall (as I guess is the only CC basic can use/output)

Function GETALLADAPTERS(Target2: PChar): PChar;  stdcall; External 'newnic2.dll' name 'GetAllAdapters';

export/import function names ARE case-sensitive
Target2 should be preallocated on the caller like:

var T2: string;
...
SetLength(T2, 255);
0
 

Author Comment

by:KentDRuddick
ID: 12432771


Just what I needed.

Thanks
Kent
0

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