如何实现jpg图片的导入

Question

如何能象WORD的文件菜单那样，能导入jpg图片。怎样来实现？

Answer 1

http://www.codeproject.com/bitmap/pictureshow.asp

Answer 2

LPPICTURE gpPicture;// open file
HANDLE hFile = CreateFile(szFile, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL);
_ASSERTE(INVALID_HANDLE_VALUE != hFile); // get file size
DWORD dwFileSize = GetFileSize(hFile, NULL);
_ASSERTE(-1 != dwFileSize); LPVOID pvData = NULL;
// alloc memory based on file size
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
_ASSERTE(NULL != hGlobal); pvData = GlobalLock(hGlobal);
_ASSERTE(NULL != pvData); DWORD dwBytesRead = 0;
// read file and store in global memory
BOOL bRead = ReadFile(hFile, pvData, dwFileSize, &dwBytesRead, NULL);
_ASSERTE(FALSE != bRead);
GlobalUnlock(hGlobal);
CloseHandle(hFile); LPSTREAM pstm = NULL;
// create IStream* from global memory
HRESULT hr = CreateStreamOnHGlobal(hGlobal, TRUE, &pstm);
_ASSERTE(SUCCEEDED(hr) && pstm); // Create IPicture from image file
if (gpPicture)
gpPicture->Release();
hr = ::OleLoadPicture(pstm, dwFileSize, FALSE, IID_IPicture, (LPVOID *)&gpPicture);
_ASSERTE(SUCCEEDED(hr) && gpPicture);
pstm->Release(); InvalidateRect(ghWnd, NULL, TRUE);long hmWidth;
long hmHeight;
gpPicture->get_Width(&hmWidth);
gpPicture->get_Height(&hmHeight);
// convert himetric to pixels
int nWidth = MulDiv(hmWidth, GetDeviceCaps(hdc, LOGPIXELSX), HIMETRIC_INCH);
int nHeight = MulDiv(hmHeight, GetDeviceCaps(hdc, LOGPIXELSY), HIMETRIC_INCH);
RECT rc;
GetClientRect(hWnd, &rc);
// display picture using IPicture::Render
gpPicture->Render(hdc, 0, 0, nWidth, nHeight, 0, hmHeight, hmWidth, -hmHeight, &rc);

Answer 3

HRESULT ShowPic(CString lpstrFile, HWND hwnd, int nScrWidth, int nScrHeight)
{
HDC hDC_Temp = ::GetDC(hwnd); IPicture *pPic;
IStream *pStm; BOOL bResult; HANDLE hFile = NULL;
DWORD dwFileSize, dwByteRead; // 打开硬盘中的图形文件 
hFile = CreateFile(lpstrFile,
GENERIC_READ,
FILE_SHARE_READ,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL); if (hFile != INVALID_HANDLE_VALUE)
{ 
dwFileSize = GetFileSize(hFile, NULL); // 获取文件字节数 

if (dwFileSize == 0xFFFFFFFF)
return E_FAIL;
} 
else
{ 
return E_FAIL;
}  // 分配全局存储空间 
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
LPVOID pvData = NULL; if (hGlobal == NULL)
return E_FAIL; if ((pvData = GlobalLock(hGlobal)) == NULL) // 锁定分配内存块 
return E_FAIL; ReadFile(hFile, pvData, dwFileSize, &dwByteRead, NULL); // 把文件读入内存缓冲区 GlobalUnlock(hGlobal); CreateStreamOnHGlobal(hGlobal, TRUE, &pStm); // 装入图形文件 
bResult=OleLoadPicture(pStm, dwFileSize, TRUE, IID_IPicture, (LPVOID*)&pPic); if(FAILED(bResult))
return E_FAIL; OLE_XSIZE_HIMETRIC hmWidth; // 图片的真实宽度 
OLE_YSIZE_HIMETRIC hmHeight; // 图片的真实高度 
pPic->get_Width(&hmWidth);
pPic->get_Height(&hmHeight); // 将图形输出到屏幕上(有点像BitBlt)
bResult = pPic->Render(hDC_Temp,
0,
0,
nScrWidth,
nScrHeight,
0,
hmHeight,
hmWidth,
-hmHeight,
NULL); pPic->Release();
pStm->Release(); CloseHandle(hFile); // 关闭打开的文件  if (SUCCEEDED(bResult))
{ 
return S_OK;
}
else 
{ 
return E_FAIL;
} 
}