MFC子文档动态显示jpg图片方法

1、为对话框添加#include<Afxwin.h>头文件
2、将picture控件的ID改为IDC_PICTURE
3、为对话框添加HICON m_hIcon变量和CString str，并在构造函数中定义 str = "lew";
m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
4、为按钮添加消息函数
代码如下：
void CMyDlg7::OnBnClickedButton1()
{
// TODO: 在此添加控件通知处理程序代码
CFileDialog* filedialog;
filedialog = new CFileDialog(TRUE,"jpg","*.jpg",OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,"JPEG文件(*.jpg)|                                      *.jpg|BMP文件(*.bmp)|*.bmp||",NULL);
if(filedialog->DoModal()==IDOK)
{
str = filedialog->GetPathName();
Invalidate();
}
delete (filedialog);
}
5、重载OnPaint函数
代码如下：
void CMyDlg7::OnPaint()
{
if(IsIconic()) 
{
CPaintDC dc(this);                //device context for painting
SendMessage(WM_ICONERASEBKGND,(WPARAM)dc.GetSafeHdc(),0);
//Center icon in client rectangle
int cxIcon = GetSystemMetrics(SM_CXICON);
int cyIcon = GetSystemMetrics(SM_CYICON);
CRect rect;