mfc加载PNG图片

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方法一（GDI+）：

//本地加载
Image image(_T("1.png")); 


//资源加载
BOOL ImageFromIDResource(UINT nID, LPCTSTR sTR,Image *&pImg)
{
	HINSTANCE hInst = AfxGetResourceHandle();
	HRSRC hRsrc = ::FindResource (hInst,MAKEINTRESOURCE(nID),sTR); // type
	if (!hRsrc)
		return FALSE;
	// load resource into memory
	DWORD len = SizeofResource(hInst, hRsrc);
	BYTE* lpRsrc = (BYTE*)LoadResource(hInst, hRsrc);
	if (!lpRsrc)
		return FALSE;
	// Allocate global memory on which to create stream
	HGLOBAL m_hMem = GlobalAlloc(GMEM_FIXED, len);
	BYTE* pmem = (BYTE*)GlobalLock(m_hMem);
	memcpy(pmem,lpRsrc,len);
	GlobalUnlock(m_hMem);
	IStream* pstm;
	CreateStreamOnHGlobal(m_hMem,FALSE,&pstm);
	// load from stream
	pImg=Gdiplus::Image::FromStream(pstm);
	// free/release stuff
	pstm->Release();
	FreeResource(lpRsrc);
	GlobalFree(m_hMem);
	return TRUE;
}


//绘制
Graphics graphics(pDC->m_hDC); 
//用本地或者资源加载image
graphics.DrawImage(&image, 0, 0, image.GetWidth(), image.GetHeight());

方法二（CImage）：

//本地加载
CImage Image;
Image.Load(strPath);

//资源加载
BOOL LoadImageFromResource(CImage *pImage, UINT nResID,LPCTSTR lpTyp)
{
	if ( pImage == NULL) 
		return false;
	pImage->Destroy();
	// 查找资源
	HRSRC hRsrc = ::FindResource(AfxGetResourceHandle(), MAKEINTRESOURCE(nResID), lpTyp);
	if (hRsrc == NULL) 
		return false;
	// 加载资源
	HGLOBAL hImgData = ::LoadResource(AfxGetResourceHandle(), hRsrc);
	if (hImgData == NULL)
	{
		::FreeResource(hImgData);
		return false;
	}
	// 锁定内存中的指定资源
	LPVOID lpVoid = ::LockResource(hImgData);
	LPSTREAM pStream = NULL;
	DWORD dwSize = ::SizeofResource(AfxGetResourceHandle(), hRsrc);
	HGLOBAL hNew = ::GlobalAlloc(GHND, dwSize);
	LPBYTE lpByte = (LPBYTE)::GlobalLock(hNew);
	::memcpy(lpByte, lpVoid, dwSize);
	// 解除内存中的指定资源
	::GlobalUnlock(hNew);
	// 从指定内存创建流对象
	HRESULT ht = ::CreateStreamOnHGlobal(hNew, TRUE, &pStream);
	if ( ht != S_OK )
	{
		GlobalFree(hNew);
	}
	else
	{
		// 加载图片
		pImage->Load(pStream);
		GlobalFree(hNew);
	}
	// 释放资源
	::FreeResource(hImgData);
	return true;
}

//绘制
CDC *pDC = GetDC();
CImage Image;

//用本地或者资源加载Image

if (Image.IsNull())
{
	MessageBox(_T("没加载成功"));
	return -1;
}
//注意：一定要将透明通道处理一下
if (Image.GetBPP() == 32) //确认该图像包含Alpha通道
{
	int i;
	int j;
	for (i = 0; i < Image.GetWidth(); i++)
	{
		for (j = 0; j < Image.GetHeight(); j++)
		{
			byte *pByte = (byte *)Image.GetPixelAddress(i, j);
			pByte[0] = pByte[0] * pByte[3] / 255;
			pByte[1] = pByte[1] * pByte[3] / 255;
			pByte[2] = pByte[2] * pByte[3] / 255;
		}
	}
}
Image.Draw(pDC->m_hDC, 0, 0);
Image.Destroy();
ReleaseDC(pDC);