MFC句柄和指针转化,帮忙看下哪里出错了

Question

//子窗体里的代码
HWND hwnd= this->GetParent()->GetSafeHwnd();//获取父窗体的句柄
CMyTabExampleDlg *pParentdlg=(CMyTabExampleDlg*)GlobalLock(hwnd);//转换成对象指针
pParentdlg->DestroyWindow();//销毁主窗体

Answer 1

CWnd* pParent = this->GetParent();
pParnet->DestroyWindow();

Answer 2

CWnd* wnd = CWnd::FromHandle(hwnd);
wnd->DestroyWindow();

Answer 3

都报错：Debug Assertion Failed

Answer 4

HWND hwnd= this->GetParent()->GetSafeHwnd();//获取父窗体的句柄 
if(hwnd)
   DestroyWindow(hwnd);
BOOL DestroyWindow(
  HWND hWnd   // handle to window to destroy
);