asked on

Function in DLL got Access Violation

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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ChristianWimmer

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cebasso

ASKER

Thanks :DD
Regards,
Carlos

JosephGlosz

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.

cebasso

ASKER

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