MFC打开文件解决方案

MFC打开文件
我加一个按钮，打开文件的功能，直接在该按钮的消息响应函数写
void CTest02Dlg::OnButton1() 
{
// TODO: Add your control notification handler code here
CFileDialog myFileDialog;
CString szFilters,pathName,filename;

szFilters="my文档(*.my)|*.my | 所有文档(*.*)|*.* ||";
myFileDialog = (true,"my","*.my",OFN_HIDEREADONLY|OFN_FILEMUSTEXIST,szFilters,this);

if(myFileDialog.DoModal()==IDOK)
{
pathName=myFileDialog.GetPathName();
filename=myFileDialog.GetFileName();
SetWindowText(filename);
MessageBox(pathName);
}

}
提示错误：
E:\C++ Data\test02\test02Dlg.cpp(176) : error C2512: 'CFileDialog' : no appropriate default constructor available
E:\C++ Data\test02\test02Dlg.cpp(180) : error C2582: 'CFileDialog' : 'operator =' function is unavailable
要怎样才能行，是不是自己还得写一个类，继承CFileDialog

[解决办法]

C/C++ code

explicit CFileDialog(   BOOL bOpenFileDialog,   LPCTSTR lpszDefExt = NULL,   LPCTSTR lpszFileName = NULL,   DWORD dwFlags = OFN_HIDEREADONLY | OFN_OVERWRITEPROMPT,   LPCTSTR lpszFilter = NULL,   CWnd* pParentWnd = NULL,   DWORD dwSize = 0);