请教各位高手怎样用win32 Application编写应用程序？

我有于下代码：
#include<afxwin.h>
#include<afxext.h>#define SeedRand()  srand((UINT)::GetTickCount())class CMyApp:public CWinApp
{
public:
virtual BOOL Initance();
};
class CMainWnd:public CFrameWnd
{
public:
CMainWnd();
afx_msg void OnTimer(UINT IDTimer);
DECLARE_MESSAGE_MAP();protected:
COLORREF GetRandColor();
UINT MapRand(UINT nMax);
void Growing_Ellipse(CClientDC *pDC);protected:
CPoint m_rect_E;
int m_R_rect;
int m_C_rect;
};
BEGIN_MESSAGE_MAP(CMainWnd,CFrameWnd)
   ON_WM_TIMER()
END_MESSAGE_MAP()
CMainWnd::CMainWnd()
{
m_C_rect=10;
m_R_rect=30;
m_rect_E.x=320;
m_rect_E.y=240;
SeedRand();
}COLORREF CMainWnd::GetRandColor()
{
return RGB(MapRand(255),MapRand(255),MapRand(255));
}UINT CMainWnd::MapRand(UINT nMax)
{
UINT random=rand();
float Aver=(float)nMax/RAND_MAX;
return (UINT)((float)random*Aver+0.5f);
}
void CMainWnd::Growing_Ellipse(CClientDC *pDC)
{
CBrush ColorBrush(GetRandColor());
pDC->SelectObject(&ColorBrush); if(m_rect_E.x-m_R_rect<=0)
m_R_rect=30;
// draw ellipse
pDC->Ellipse(m_rect_E.x-m_R_rect,m_rect_E.y-long(m_R_rect*480/640),
m_rect_E.x+m_R_rect,m_rect_E.y+long(m_R_rect*480/640));
m_R_rect+=m_C_rect;
}
void CMainWnd::OnTimer(UINT IDTimer)
{
CClientDC dc(this);
Growing_Ellipse(&dc);
}
BOOL CMyApp::Initance()
{
CMainWnd *pFrame=new CMainWnd;
pFrame->Create(0,"Graphics Demos",WS_POPUPWINDOW|WS_DLGFRAME,CRect(0,0,640,480));
pFrame->ShowWindow(m_nCmdShow);
pFrame->UpdateWindow();
m_pMainWnd=pFrame;
pFrame->SetTimer(10,15,NULL);
return TRUE;
}CMyApp Graphics;
但是在link时出现于下的ERROR：
Linking...
nafxcwd.lib(thrdcore.obj) : error LNK2001: unresolved external symbol __endthreadex
nafxcwd.lib(thrdcore.obj) : error LNK2001: unresolved external symbol __beginthreadex
Debug/Ellipse.exe : fatal error LNK1120: 2 unresolved externals
Error executing link.exe.
请高手们指点一二，小弟多谢了！！！