调用dll的代码：

extern "C" __declspec(dllexport) int __stdcall Deposit(String pers_no);

。。。。

  int _stdcall(*ddd)(String);
  HINSTANCE dd = LoadLibrary("Deposit.dll");
  (FARPROC &)ddd = GetProcAddress(dd,"Deposit");
  Caption=IntToStr(ddd("10004447"));
  FreeLibrary(dd);

奇怪的是delphi调用正常，BCB写的调用缺报错“尚未调用CoInitialize”，原来dll用到了ado控件，属于com组件，使用时必须初始化

CoInitialize(NULL);
 Tdm *dm = new Tdm(NULL);
 if(!dm->cn->Connected)
  dm->cn->Connected = true;
 dm->q->ExecSQL();
 dm->cn->Connected = false;
 delete dm;
 CoUninitialize();