c++做的供其他程序使用的动态链接库(袁振德)

// pb.cpp : Defines the initialization routines for the DLL.
//

#include "stdafx.h"
#include <string.h>
#include "pb.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

//
// Note!
//
//  If this DLL is dynamically linked against the MFC
//  DLLs, any functions exported from this DLL which
//  call into MFC must have the AFX_MANAGE_STATE macro
//  added at the very beginning of the function.
//
//  For example:
//
//  extern "C" BOOL PASCAL EXPORT ExportedFunction()
//  {
//   AFX_MANAGE_STATE(AfxGetStaticModuleState());
//   // normal function body here
//  }
//
//  It is very important that this macro appear in each
//  function, prior to any calls into MFC.  This means that
//  it must appear as the first statement within the
//  function, even before any object variable declarations
//  as their constructors may generate calls into the MFC
//  DLL.
//
//  Please see MFC Technical Notes 33 and 58 for additional
//  details.
//

/////////////////////////////////////////////////////////////////////////////
// CPbApp

BEGIN_MESSAGE_MAP(CPbApp, CWinApp)
 //{{AFX_MSG_MAP(CPbApp)
  // NOTE - the ClassWizard will add and remove mapping macros here.
  //    DO NOT EDIT what you see in these blocks of generated code!
 //}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CPbApp construction

CPbApp::CPbApp()
{
 // TODO: add construction code here,
 // Place all significant initialization in InitInstance
}

/////////////////////////////////////////////////////////////////////////////
// The one and only CPbApp object

CPbApp theApp;
char* p = NULL;

extern "C" _declspec(dllexport)
char*   _stdcall  output_number(char* aa)
{

 CString s = aa;
 s += "abcd";
 
 int nlen = s.GetLength();
 if(p != NULL)
 {
  delete[] p;
  p = NULL;
 }
 p = new char[nlen + 1];
 
 p[nlen] = 0;
 
 memcpy(p,s.GetBuffer(0),s.GetLength());
 
 
 
 return p;

 
}
extern "C" _declspec(dllexport)
char* _stdcall   deleteaa()
{
 if(p != NULL)
 {
  delete[] p;
  p = NULL;
 }
 char* a = "0";
 return a;
}

//CString s = a;
//s += "abcd";
//
//int nlen = s.GetLength();
//char* p = new char[nlen + 1];
//
//p[nlen] = 0;
//
//memcpy(p,s.GetBuffer(0),s.GetLength());
//
//
//
//return p;