1、MFC对话框显示BMP图片
我们先从简单的开始吧.先分一个类:
(一) 非http://topic.csdn.net/u/20090410/10/ad7a5afe-c906-45ff-a673-f601e2ec05be.html
2、MFC对话框显示JPEG图片
放在对话框的OnPaint里
1 CDC* pDC;
2 pDC=GetDC();
3 ShowPicture(pDC,"c:\\12.jpg",0,0,200,100);
4
5
6
7 #define HIMETRIC_INCH 2540
8 LPPICTURE gpPicture;
9 void CCDMADlg::ShowPicture(CDC *pDC, CString m_strBRoute, int x, int y, int width, int height)
10 {
11 HANDLE hFile =CreateFile(m_strBRoute, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL);
12 _ASSERTE(INVALID_HANDLE_VALUE != hFile);
13
14 // 取得文件大小
15 DWORD dwFileSize = GetFileSize(hFile, NULL);
16 _ASSERTE(-1 != dwFileSize);
17 LPVOID pvData = NULL;
18 //根据文件大小分配内存
19 HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
20 _ASSERTE(NULL != hGlobal);
21 pvData = GlobalLock(hGlobal);
22 _ASSERTE(NULL != pvData);
23 DWORD dwBytesRead = 0;
24 //读取文件并存入全局内存
25 BOOL bRead = ReadFile(hFile, pvData, dwFileSize, &dwBytesRead, NULL);
26 _ASSERTE(FALSE != bRead);
27 GlobalUnlock(hGlobal);
28 CloseHandle(hFile);
29 LPSTREAM pstm = NULL;
30 // 通过全局内存创建 IStream* 的指针
31 HRESULT hr = CreateStreamOnHGlobal(hGlobal, TRUE, &pstm);
32 _ASSERTE(SUCCEEDED(hr) && pstm);
33 //通过图形文件创建IPicture 对象
34 if (gpPicture)
35 gpPicture->Release();
36 hr = OleLoadPicture(pstm, dwFileSize, FALSE, IID_IPicture, (LPVOID *)&gpPicture);
37 _ASSERTE(SUCCEEDED(hr) && gpPicture);
38 pstm->Release();
39 HDC hdc;
40 hdc=pDC->GetSafeHdc();
41 if (gpPicture)
42 {
43 // 取得图片的宽和高
44 long hmWidth;
45 long hmHeight;
46 gpPicture->get_Width(&hmWidth);
47 gpPicture->get_Height(&hmHeight);
48 //宽高转换为象素
49 int nWidth = MulDiv(hmWidth, GetDeviceCaps(hdc, LOGPIXELSX), HIMETRIC_INCH);
50 int nHeight = MulDiv(hmHeight, GetDeviceCaps(hdc, LOGPIXELSY), HIMETRIC_INCH);
51 RECT rc;
52 GetClientRect(&rc);/*取得客户区*/
53 gpPicture->Render(hdc, x,y, (int)height*hmWidth/hmHeight,height, 0, hmHeight, hmWidth, -hmHeight, &rc);
54 /*显示图片*/
55 }
57 }
2 pDC=GetDC();
3 ShowPicture(pDC,"c:\\12.jpg",0,0,200,100);
4
5
6
7 #define HIMETRIC_INCH 2540
8 LPPICTURE gpPicture;
9 void CCDMADlg::ShowPicture(CDC *pDC, CString m_strBRoute, int x, int y, int width, int height)
10 {
11 HANDLE hFile =CreateFile(m_strBRoute, GENERIC_READ, 0, NULL, OPEN_EXISTING, 0, NULL);
12 _ASSERTE(INVALID_HANDLE_VALUE != hFile);
13
14 // 取得文件大小
15 DWORD dwFileSize = GetFileSize(hFile, NULL);
16 _ASSERTE(-1 != dwFileSize);
17 LPVOID pvData = NULL;
18 //根据文件大小分配内存
19 HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, dwFileSize);
20 _ASSERTE(NULL != hGlobal);
21 pvData = GlobalLock(hGlobal);
22 _ASSERTE(NULL != pvData);
23 DWORD dwBytesRead = 0;
24 //读取文件并存入全局内存
25 BOOL bRead = ReadFile(hFile, pvData, dwFileSize, &dwBytesRead, NULL);
26 _ASSERTE(FALSE != bRead);
27 GlobalUnlock(hGlobal);
28 CloseHandle(hFile);
29 LPSTREAM pstm = NULL;
30 // 通过全局内存创建 IStream* 的指针
31 HRESULT hr = CreateStreamOnHGlobal(hGlobal, TRUE, &pstm);
32 _ASSERTE(SUCCEEDED(hr) && pstm);
33 //通过图形文件创建IPicture 对象
34 if (gpPicture)
35 gpPicture->Release();
36 hr = OleLoadPicture(pstm, dwFileSize, FALSE, IID_IPicture, (LPVOID *)&gpPicture);
37 _ASSERTE(SUCCEEDED(hr) && gpPicture);
38 pstm->Release();
39 HDC hdc;
40 hdc=pDC->GetSafeHdc();
41 if (gpPicture)
42 {
43 // 取得图片的宽和高
44 long hmWidth;
45 long hmHeight;
46 gpPicture->get_Width(&hmWidth);
47 gpPicture->get_Height(&hmHeight);
48 //宽高转换为象素
49 int nWidth = MulDiv(hmWidth, GetDeviceCaps(hdc, LOGPIXELSX), HIMETRIC_INCH);
50 int nHeight = MulDiv(hmHeight, GetDeviceCaps(hdc, LOGPIXELSY), HIMETRIC_INCH);
51 RECT rc;
52 GetClientRect(&rc);/*取得客户区*/
53 gpPicture->Render(hdc, x,y, (int)height*hmWidth/hmHeight,height, 0, hmHeight, hmWidth, -hmHeight, &rc);
54 /*显示图片*/
55 }
57 }