在VC6工程的Picture控件上显示JPG等图片，且图片随控件大小改变

1、Picture.h文件

////////////////////////////////////////////////////////////////
// If this code works, it was written by Paul DiLascia.
// If not, I don't know who wrote it.
// Compiles with Visual C++ 6.0 for Windows 98 and probably Windows 2000 too.
// Set tabsize = 3 in your editor.
//
#pragma once
#include <atlbase.h>

//////////////////
// Picture object--encapsulates IPicture
//
class CPicture {
public:
 CPicture();
 ~CPicture();

 // Load frm various sosurces
 BOOL Load(UINT nIDRes);
 BOOL Load(LPCTSTR pszPathName);
 BOOL Load(CFile& file);
 BOOL Load(CArchive& ar);
 BOOL Load(IStream* pstm);

 // render to device context
 BOOL Render(CDC* pDC, CRect rc=CRect(0,0,0,0),
  LPCRECT prcMFBounds=NULL) const;

 CSize GetImageSize(CDC* pDC=NULL) const;

 operator IPicture*() {
  return m_spIPicture;
 }

 void GetHIMETRICSize(OLE_XSIZE_HIMETRIC& cx, OLE_YSIZE_HIMETRIC& cy) const {
  cx = cy = 0;
  const_cast<CPicture*>(this)->m_hr = m_spIPicture->get_Width(&cx);
  ASSERT(SUCCEEDED(m_hr));
  const_cast<CPicture*>(this)->m_hr = m_spIPicture->get_Height(&cy);
  ASSERT(SUCCEEDED(m_hr));
 }

 void Free() {
  if (m_spIPicture) {
   m_spIPicture.Release();
  }
 }

protected:
 CComQIPtr<IPicture>m_spIPicture;   // ATL smart pointer to IPicture
 HRESULT m_hr;         // last error code
};
2、Picture.cpp 

////////////////////////////////////////////////////////////////
// If this code works, it was written by Paul DiLascia.
// If not, I don't know who wrote it.
// Compiles with Visual C++ 6.0 for Windows 98 and probably Windows 2000 too.
// Set tabsize = 3 in your editor.
//
#include "StdAfx.h"
#include "Picture.h"

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

////////////////////////////////////////////////////////////////
// CPicture implementation
//

CPicture::CPicture()
{
}

CPicture::~CPicture()
{
}

//////////////////
// Load from resource. Looks for "IMAGE" type.
//
BOOL CPicture::Load(UINT nIDRes)
{
 // find resource in resource file
 HINSTANCE hInst = AfxGetResourceHandle();
 HRSRC hRsrc = ::FindResource(hInst,
  MAKEINTRESOURCE(nIDRes),
  _T("IMAGE")); // type
 if (!hRsrc)
  return FALSE;

 // load resource into memory
 DWORD len = SizeofResource(hInst, hRsrc);
 BYTE* lpRsrc = (BYTE*)LoadResource(hInst, hRsrc);
 if (!lpRsrc)
  return FALSE;

 // create memory file and load it
 CMemFile file(lpRsrc, len);
 BOOL bRet = Load(file);
 FreeResource(hRsrc);
 GlobalFree(lpRsrc);
 return bRet;
}

//////////////////
// Load from path name.
//
BOOL CPicture::Load(LPCTSTR pszPathName)
{
 CFile file;
 if (!file.Open(pszPathName, CFile::modeRead|CFile::shareDenyWrite))
  return FALSE;
 BOOL bRet = Load(file);
 file.Close();
 return bRet;
}

//////////////////
// Load from CFile
//
BOOL CPicture::Load(CFile& file)
{
 CArchive ar(&file, CArchive::load | CArchive::bNoFlushOnDelete);
 return Load(ar);
}

//////////////////
// Load from archive--create stream and load from stream.
//
BOOL CPicture::Load(CArchive& ar)
{
 CArchiveStream arcstream(&ar);
 return Load((IStream*)&arcstream);
}

//////////////////
// Load from stream (IStream). This is the one that really does it: call
// OleLoadPicture to do the work.
//
BOOL CPicture::Load(IStream* pstm)
{
 Free();
 HRESULT hr = OleLoadPicture(pstm, 0, FALSE,
  IID_IPicture, (void**)&m_spIPicture);
 ASSERT(SUCCEEDED(hr) && m_spIPicture); 
 return TRUE;
}

//////////////////
// Render to device context. Covert to HIMETRIC for IPicture.
//
BOOL CPicture::Render(CDC* pDC, CRect rc, LPCRECT prcMFBounds) const
{
 ASSERT(pDC);

 if (rc.IsRectNull()) {
  CSize sz = GetImageSize(pDC);
  rc.right = sz.cx;
  rc.bottom = sz.cy;
 }
 long hmWidth,hmHeight; // HIMETRIC units
 GetHIMETRICSize(hmWidth, hmHeight);
 m_spIPicture->Render(*pDC, rc.left, rc.top, rc.Width(), rc.Height(),
  0, hmHeight, hmWidth, -hmHeight, prcMFBounds);

 return TRUE;
}

//////////////////
// Get image size in pixels. Converts from HIMETRIC to device coords.
//
CSize CPicture::GetImageSize(CDC* pDC) const
{
 if (!m_spIPicture)
  return CSize(0,0);
 
 LONG hmWidth, hmHeight; // HIMETRIC units
 m_spIPicture->get_Width(&hmWidth);
 m_spIPicture->get_Height(&hmHeight);
 CSize sz(hmWidth,hmHeight);
 if (pDC==NULL) {
  CWindowDC dc(NULL);
  dc.HIMETRICtoDP(&sz); // convert to pixels
 } else {
  pDC->HIMETRICtoDP(&sz);
 }
 return sz;
}

3、在需要显示图片的页面，比如PictureReview.h中包含Picture.h头文件，且添加成员变量CPicture m_pic;

然后重载OnPaint()函数，在该函数中加入

m_pic.Load(theApp.m_strSelectNamePath);
 CRect crt;
 m_ctrPic.GetClientRect(&crt);
 CRect rc;
 rc.IntersectRect(&crt,&crt);
 m_pic.Render(&dc,rc);

其中theApp.m_strSelectNamePath是传递图片的具体路径，m_ctrPic是Picture控件的对象CStatic m_ctrPic;