//************************************
// 方法说明: 显示JPG和GIF、BMP图片
// 参数说明: CDC * pDC 设备环境对象
// 参数说明: CString strPath 要显示的图片路径
// 参数说明: int x 要显示的X位置
// 参数说明: int y 要显示的Y位置
// 返回值: BOOL 成功返回TRUE,否则返回FALSE
//************************************
BOOL CShowJpgDlg::ShowJpgGif(CDC* pDC,CString strPath, int x, int y)
{
CFileStatus fstatus;
CFile file;
ULONGLONG cb;
// 打开文件并检测文件的有效性
if (!file.Open(strPath,CFile::modeRead))
{
return FALSE;
}
if (!file.GetStatus(strPath,fstatus))
{
return FALSE;
}
if ((cb =fstatus.m_size)<=0)
{
return FALSE;
}
// 根据文件大小分配内存空间,记得释放内存
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, (unsigned int)cb);
if (hGlobal== NULL)
{
return FALSE;
}
// 锁定刚才分配的内存空间
LPVOID pvData = NULL;
pvData = GlobalLock(hGlobal);
if (pvData == NULL)
{
GlobalFree(hGlobal); // 记得释放内存
return FALSE;
}
// 将文件放到流中
IStream *pStm;
file.Read(pvData,(unsigned int)cb);
GlobalUnlock(hGlobal);
CreateStreamOnHGlobal(hGlobal, TRUE, &pStm);
// 从流中加载图片
// 显示JPEG和GIF格式的图片，GIF只能显示一帧，还不能显示动画，
// 要显示动画GIF请使用ACTIVE控件。
IPicture *pPic;
if(OleLoadPicture(pStm,(LONG)fstatus.m_size,TRUE,IID_IPicture,(LPVOID*)&pPic)!=S_OK)
{
GlobalFree(hGlobal); // 记得释放内存
return FALSE;
}
//获取图像宽和高,注意这里的宽和高不是图像的分辨率
OLE_XSIZE_HIMETRIC hmWidth;
OLE_YSIZE_HIMETRIC hmHeight;
pPic->get_Width(&hmWidth);
pPic->get_Height(&hmHeight);
// 将图像宽度和高度单位转化为像素单位
//#define HIMETRIC_PER_INCH 2540
//int nPicWidth = MulDiv(hmWidth, GetDeviceCaps(GetDC()->m_hDC, LOGPIXELSX),2540);
//int nPicHeight = MulDiv(hmHeight, GetDeviceCaps(GetDC()->m_hDC, LOGPIXELSY),2540);
//HRESULT Render(
// HDC hdc, //Handle of device context on which to render the image
// long x, //Horizontal position of image in hdc
// long y, //Vertical position of image in hdc
// long cx, //Horizontal dimension of destination rectangle
// long cy, //Vertical dimension of destination rectangle
// OLE_XPOS_HIMETRIC xSrc, //Horizontal offset in source picture
// OLE_YPOS_HIMETRIC ySrc, //Vertical offset in source picture
// OLE_XSIZE_HIMETRIC cxSrc, //Amount to copy horizontally in source picture
// OLE_YSIZE_HIMETRIC cySrc, //Amount to copy vertically in source picture
// LPCRECT prcWBounds //Pointer to position of destination for a metafile hdc
// );
//use render function display image
RECT rtWnd;
pDC->GetWindow()->GetWindowRect(&rtWnd);
int iWndWidth=rtWnd.right-rtWnd.left;
int iWndHeight=rtWnd.bottom-rtWnd.top;
if(FAILED(pPic->Render(*pDC,x,y,iWndWidth,iWndHeight,0,hmHeight,hmWidth,-hmHeight,NULL)))
{
pPic->Release();
GlobalFree(hGlobal); // 记得释放内存
return false;
}
pPic->Release();
GlobalFree(hGlobal); // 记得释放内存
return true;
}
//************************************
// 方法说明: 显示JPG和GIF、BMP图片
// 参数说明: CDC * pDC 设备环境对象
// 参数说明: CString strPath 要显示的图片路径
// 参数说明: int x 要显示的X位置
// 参数说明: int y 要显示的Y位置
// 返回值: BOOL 成功返回TRUE,否则返回FALSE
//************************************
BOOL CShowJpgDlg::ShowImage(CDC* pDC,CString strPath, int x, int y)
{
IPicture *pPic=NULL;
OleLoadPicturePath(CComBSTR(strPath.GetBuffer()), (LPUNKNOWN)NULL, 0, 0, IID_IPicture,(LPVOID*)&pPic);
if (NULL==pPic)
{
return FALSE;
}
// 获取图像宽和高,注意这里的宽和高不是图像的分辨率
OLE_XSIZE_HIMETRIC hmWidth;
OLE_YSIZE_HIMETRIC hmHeight;
pPic->get_Width(&hmWidth);
pPic->get_Height(&hmHeight);
// 将图像宽度和高度单位转化为像素单位
//#define HIMETRIC_PER_INCH 2540
//int nPicWidth = MulDiv(hmWidth, GetDeviceCaps(GetDC()->m_hDC, LOGPIXELSX),2540);
//int nPicHeight = MulDiv(hmHeight, GetDeviceCaps(GetDC()->m_hDC, LOGPIXELSY),2540);
// 获取显示图片窗口的宽度和高度
RECT rtWnd;
pDC->GetWindow()->GetWindowRect(&rtWnd);
int iWndWidth=rtWnd.right-rtWnd.left;
int iWndHeight=rtWnd.bottom-rtWnd.top;
if(FAILED(pPic->Render(*pDC,x,y,iWndWidth,iWndHeight,0,hmHeight,hmWidth,-hmHeight,NULL)))
{
pPic->Release();
return false;
}
//记得释放资源，不然会导致内存泄露
pPic->Release();
return true;
}
//************************************
// 方法说明: 浏览图片
// 返回值: void
//************************************
void CShowJpgDlg::OnBnClickedBtnBrowse()
{
// TODO: Add your control notification handler code here
CFileDialog dlg(TRUE,"jpg","*.jpg", OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,
"JPEG文件(*.jpg)|*.jpg|GIF文件(*.gif)|*.gif|bmp文件(*.bmp)|*.bmp|",NULL);
if(dlg.DoModal()==IDOK)
{
SetDlgItemText(IDC_TXT_PATH,dlg.GetPathName());
//设置静态控件的样式，使其可以使用位图，并使位图显示居中
((CStatic*)GetDlgItem(IDC_STATIC_IMG))-> ModifyStyle(0xF,SS_BITMAP|SS_CENTERIMAGE);
CDC *pDC=NULL;
pDC=GetDlgItem(IDC_STATIC_IMG)->GetDC();
//ShowJpgGif(pDC,dlg.GetPathName(),0,0);
ShowImage(pDC,dlg.GetPathName(),0,0);
ReleaseDC(pDC);// 记得释放资源，不然会导致内存泄露
}
}
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
放在对话框的OnPaint里
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 }