The DLL I have created uses a TTimer to update some variables. when I make a call to the DLL it returns the correct values only the first time its called after the first call it returns the same values. reason for them being the same values is that the TTimer is not refreshing the values. now this problem occures when i use the Delphi DLL with a C++ applcation. (for reason unknown this problem does not occure with VB.NET)
this is a problem i have had for a while know and still have no answer for. the link below is one to another fourm that shows some bikering between me and another person about this problem.
feel free to pitch in with some help.
example code, not the actual code I am having the problem with:
library DelphiDLL;
uses Windows, extctrls, SysUtils, Classes;
//------------------------------------------------------------------------------
type TTicker = class(TTimer)
public
Value: Integer;
procedure Tick(Sender: TObject);
end;
procedure TTicker.Tick (Sender: TObject);
begin
Value := Value + 1;
end;
//------------------------------------------------------------------------------
var g_ticker: TTicker;
function GetClockValue(): Integer; export; stdcall;
begin
Result := g_ticker.Value;
end;
exports GetClockValue;
begin
g_ticker := TTicker.Create(nil);
g_ticker.OnTimer := g_ticker.Tick;
g_ticker.Value := 1;
g_ticker.Interval := 100;
g_ticker.Enabled := True;
end.
c++ code
#include <windows.h>
#include <stdio.h>
int main()
{
HINSTANCE lib = LoadLibrary("DelphiDLL\\DelphiDLL.dll");
if (lib)
{
typedef int (__stdcall * ClockProc)();
ClockProc GetClockValue = (ClockProc) GetProcAddress(lib, "GetClockValue");
if (GetClockValue)
{
int time;
do {
time = GetClockValue();
printf("%d\n", time);
} while (time < 100);
}
FreeLibrary(lib);
}
return 0;
} 
Aug 25th, 2004, 8:42 PM
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