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Function in DLL got Access Violation

Posted on 2008-10-08
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1,150 Views
Last Modified: 2012-08-13
Hello,

Whats wrong in my code?

I got access violation after Close the form, a empty form...

What is wrong here?

Best Regards,
Carlos


[EXE]
 

function CallMyDLLFunc: Boolean;

type

  TMyDLLFunc = record

    Func: function: BOOL; StdCall;

    hLib: THandle;

  end;

var

  MyDLLFunc: TMyDLLFunc;

begin

  Result := False;

  with MyDLLFunc do

  begin

    hLib := LoadLibrary(PChar('dll.dll'));

    if hLib <> 0 then

    begin

      @Func := GetProcAddress(hLib, 'MyDLLFunc');

      if Assigned(Func) then

      Result := Func;

      FreeLibrary(hLib);

    end;

  end;

end;
 

procedure TForm1.Button1Click(Sender: TObject);

begin

  if CallMyDLLFunc then

  ShowMessage('OK');

end;
 

----------------------------------------------------------------------

[DLL]
 

function MyDLLFunc: BOOL; StdCall;

begin

  Result := False;

  Form1 := TForm1.Create(nil);

  try

    Form1.ShowModal;

    Result := Form1.bResult; //bResult is Boolean in Public

  finally

    Form1.Release;

    Form1 := nil;

  end;

end;
 

exports

  EULA name 'EULA';

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Question by:cebasso
  • 2
4 Comments
 
LVL 6

Accepted Solution

by:
ChristianWimmer earned 500 total points
ID: 22671734
0
 
LVL 4

Author Closing Comment

by:cebasso
ID: 31504365
Thanks :DD
Regards,
Carlos
0
 
LVL 6

Expert Comment

by:JosephGlosz
ID: 22671877
this line
     @Func := GetProcAddress(hLib, 'MyDLLFunc');

should be
     @Func := GetProcAddress(hLib, 'Eula);

then, inside your DLL, the function name should be Eula as well, so change
  function MyDLLFunc: BOOL; StdCall;
to
  function Eula: BOOL; StdCall;

Or, if you want to call the function MyDLLFunc, then you should "export" it as such.

0
 
LVL 4

Author Comment

by:cebasso
ID: 22671945
JosephGlosz thanks for reply, but i just got the code and changed the original name of the Function, its really EULA but i changed here to MyDLLFunc just as example.
Anyway my problem was solved changing .Release to .Free
Thanks anyway!
Regards!
Carlos
0

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