VC 图像控件图像显示

来源：互联网发布：乳胶沙发品牌知乎编辑：程序博客网时间：2024/05/16 23:48

使用picture控件动态显示图片方法

一 控件适应于图片尺寸

添加一个picture控件，修改ID为IDC-PICTURE,并添加一CBitmap m_bmp成员变量

在OnInitDialog()函数中添加如下代码

if(m_bmp.m_hObject!=NULL)m_bmp.DeleteObject();

//以绝对路径加载BMP图片

HBITMAPhbmp=(HBITMAP)::LoadImage(AfxGetInstanceHandle(),"1.bmp",IMAGE_BITMAP,

0,0,LR_CREATEDIBSECTION| LR_LOADFROMFILE);

if(hbmp==NULL)return false;

//获得加载位图的文件信息

m_bmp.Attach(hbmp);

DIBSECTIONds;

BITMAPINFOHEADER&bminfo=ds.dsBmih;//获得位图信息图

m_bmp.GetObject(sizeof(ds),&ds);

intcx=bminfo.biWidth;//获得位图宽度

intcy=bminfo.biHeight;//获得位图高度

//该段程序根据图象的宽和高，调整控件大小，让它正好显示一张图片

CRectrect;

GetDlgItem(IDC_PICTRUE)->GetWindowRect(&rect);//获得控件所在矩形区域

ScreenToClient(&rect);

GetDlgItem(IDC_PICTRUE)->MoveWindow(rect.left,rect.top,cx,cy,true);//调整控件大小

在OnPaint()函数中添加如下代码

//三种方法获得pictrue控件DC，图象将被绘制在控件上

CPaintDCdc(GetDlgItem(IDC_PICTRUE));

//CPaintDCdc(this);

//CDCdc;

//dc.m_hDC=::GetDC(NULL);

CRectrcclient;

GetDlgItem(IDC_PICTRUE)->GetClientRect(&rcclient);

CDCmemdc;

memdc.CreateCompatibleDC(&dc);

CBitmapbitmap;

bitmap.CreateCompatibleBitmap(&dc,rcclient.Width(),rcclient.Height());

memdc.SelectObject(&bitmap);

CWnd::DefWindowProc(WM_PAINT,(WPARAM)memdc.m_hDC,0);

CDC maskdc;

maskdc.CreateCompatibleDC(&dc);

CBitmapmaskbitmap;

maskbitmap.CreateBitmap(rcclient.Width(),rcclient.Height(),1,1,NULL);

maskdc.SelectObject(&maskbitmap);

maskdc.BitBlt(0,0,rcclient.Width(),rcclient.Height(),&memdc,rcclient.left,rcclient.top,SRCCOPY);

CBrushbrush;

brush.CreatePatternBrush(&m_bmp);

dc.FillRect(rcclient,&brush);

dc.BitBlt(rcclient.left,rcclient.top,rcclient.Width(),rcclient.Height(),&memdc,

rcclient.left,rcclient.top,SRCPAINT);

brush.DeleteObject();

二 图片适用于控件尺寸

添加一个picture控件，修改ID为IDC-PICTURE

在OnPaint()函数中添加如下代码

CWnd *pWnd=GetDlgItem(IDC_PICTRUE);//获得pictrue控件窗口的句柄

CRectrect;

pWnd->GetClientRect(&rect);//获得pictrue控件所在的举行区域

CDC*pDC=pWnd->GetDC();//获得pictrue控件的DC

IStream*pStm;

CFileStatusfstatus;

CFilefile;

LONGcb;

IPicture*pPic;//定义显示图片的接口（可显示jpg格式图片）

CStringm_sPath="1.BMP";//设置想要显示的图片

//打开图象文件，获取文件字节数

if(file.Open(m_sPath,CFile::modeRead)&& file.GetStatus(m_sPath,fstatus)

&&((cb=fstatus.m_size)!=-1))

{

//分配全局存储空间

HGLOBAL hGlobal=GlobalAlloc(GMEM_MOVEABLE,cb);

LPVOID pvData=NULL;

if(hGlobal!=NULL)

{

//锁定分配内存块

if((pvData=GlobalLock(hGlobal))!=NULL)

{

//读入文件到内存缓冲区

file.ReadHuge(pvData,cb);

GlobalUnlock(hGlobal);

CreateStreamOnHGlobal(hGlobal,true,&pStm);

}

//装载图象文件

if(SUCCEEDED(OleLoadPicture(pStm,fstatus.m_size,TRUE,IID_IPicture,(LPVOID*)&pPic)))

{

OLE_XSIZE_HIMETRIC hmWidth;

OLE_XSIZE_HIMETRIC hmHeight;

pPic->get_Width(&hmWidth);//获得图象真实宽度

pPic->get_Height(&hmHeight);//获得图象真实高度

//在控件上显示图片 pPic->Render(*pDC,0,0,rect.Width(),rect.Height(),0,hmHeight,hmWidth,-hmHeight,NULL);

pPic->Release();

}

图片显示通用模块

首先为类添加如下两个函数和一个成员变量IPicture* m_pPicture;

//图片加载函数

HRESULT LoadFromBuffer(BYTE *pBuff, int nSize)

{

boolbResult=false;

HGLOBALhGlobal=GlobalAlloc(GMEM_MOVEABLE,nSize);//分配内存空间

void*pData=GlobalLock(hGlobal);//定义图象数据指针

memcpy(pData,pBuff,nSize);

GlobalUnlock(hGlobal);//释放内存空间

IStream*pStream=NULL;//定义数据流指针

//创建数据流

if(CreateStreamOnHGlobal(hGlobal,TRUE,&pStream)==S_OK)

{

HRESULThr;//定义返回结果

if((hr=OleLoadPicture(pStream,nSize,FALSE,IID_IPicture,(LPVOID*)&m_pPicture))==S_OK)

bResult=true;

pStream->Release();//释放数据流

}

returnbResult;

}

//图片显示函数

BOOL DrawFromFile(CString filename, CDC *pDC)

{

CFilecFile;

CFileExceptione;

//打开文件

if(cFile.Open(filename,CFile::modeRead| CFile::typeBinary,&e))

{

BYTE *pBuff=new BYTE[cFile.GetLength()];//定义分配内存

if(cFile.Read(pBuff,cFile.GetLength())>0)//将文件读入缓存

LoadFromBuffer(pBuff,cFile.GetLength());

delete[]pBuff;//释放缓存

longhmWidth,hmHeight;

m_pPicture->get_Width(&hmWidth);

m_pPicture->get_Height(&hmHeight);//获取图片尺寸

intnWidth=MulDiv(hmWidth,pDC->GetDeviceCaps(LOGPIXELSX),2540);

intnHeight=MulDiv(hmHeight,pDC->GetDeviceCaps(LOGPIXELSX),2540);

//在内存中画

CDCMenDC;

CBitmapbmp;

bmp.CreateCompatibleBitmap(pDC,nWidth,nHeight);

MenDC.CreateCompatibleDC(NULL);

MenDC.SelectObject(&bmp);

m_pPicture->Render(MenDC.m_hDC,0,0,nWidth,nHeight,0,hmHeight,hmWidth,-hmHeight,NULL);

//将内存中画拷贝到目的地

pDC->BitBlt(0,0,nWidth,nHeight,&MenDC,0,0,SRCCOPY);

}

returntrue;

}

然后在OnPaint()函数中显示

void CDialogDlg::OnPaint()

{

CPaintDCdc(this); // device context for painting

if(IsIconic())

{

SendMessage(WM_ICONERASEBKGND,(WPARAM) dc.GetSafeHdc(), 0);

//Center icon in client rectangle

intcxIcon = GetSystemMetrics(SM_CXICON);

intcyIcon = GetSystemMetrics(SM_CYICON);

CRectrect;

GetClientRect(&rect);

intx = (rect.Width() - cxIcon + 1) / 2;

inty = (rect.Height() - cyIcon + 1) / 2;

//Draw the icon

dc.DrawIcon(x,y, m_hIcon);

}

else

{

CStringfilename;

filename="1.bmp";

DrawFromFile(filename,&dc);

CDialog::OnPaint();

}

VC 图像控件 图像显示

VC 图像控件图像显示