HICON与HBITMAP相互转换

1、将HBITMAP转换成HICON图标

（1）方法1：

HICON HICONFromCBitmap( CBitmap& bitmap)
{
  BITMAP bmp;
  bitmap.GetBitmap(&bmp);
  
  HDC hDC = ::GetDC(NULL);
  HBITMAP hbmMask = ::CreateCompatibleBitmap(hDC, 
    bmp.bmWidth, bmp.bmHeight);
  
  ICONINFO ii = {0};
  ii.fIcon = TRUE;
  ii.hbmColor = bitmap;
  ii.hbmMask = hbmMask;
  
  HICON hIcon = ::CreateIconIndirect(&ii);  // 一旦不再需要，注意用DestroyIcon函数释放占用的内存及资源，否则会导致内存和GDI资源的泄漏
  ::DeleteObject(hbmMask);

  ::ReleaseDC(NULL, hDC);
 return hIcon;
}

（2）方法2：（使用gdi+）

#include <gdiplus.h>
#pragma comment(lib,"GdiPlus.lib")
 
HICON CreateIcon(HBITMAP hBitmap)
{
 Gdiplus::Bitmap* pTmpBitmap=Gdiplus::Bitmap::FromHBITMAP(hBitmap,NULL);
 HICON hIcon=NULL;
 pTmpBitmap->GetHICON(&hIcon);
 delete pTmpBitmap;   // 注意此处一定要delete掉，因为调用Gdiplus::Bitmap::FromHBITMAP方法会在函数内部new一个Bitmap对象，外部要将其释放掉
 return hIcon;
}

2、 HICON转HBITMAP(注意：下面的代码有问题，后面会经过测试后再修改)

HBITMAP ConvertIconToBitmap(HICON  hIcon)
{ 
  HBITMAP   hBmp; 
  BITMAP   bmp; 
  CDC   bmpDC; 
  CDC   iconDC; 
  ICONINFO csII; 
  int bRetValue = ::GetIconInfo(hIcon, &csII); 
  if (bRetValue == FALSE)   return NULL; 

  HDC hDC = ::GetDC(NULL);
  bmpDC.Attach(hDC); 
  iconDC.CreateCompatibleDC(&bmpDC); 
  if (::GetObject(csII.hbmColor,   sizeof(BITMAP),   &bmp)) 
  { 
    DWORD       dwWidth   =   csII.xHotspot*2; 
    DWORD       dwHeight   =   csII.yHotspot*2; 
    hBmp=   ::CreateBitmap(dwWidth,   dwHeight,   bmp.bmPlanes,   
      bmp.bmBitsPixel,   NULL);
    iconDC.SelectObject(csII.hbmColor); 
    bmpDC.SelectObject(hBmp); 
    bmpDC.BitBlt(0,0,dwWidth,dwHeight,&iconDC,0,0,SRCCOPY); 
    return   hBmp; 
  }

  return NULL;
}