学习：访问Edit Control的七种方法

/*
D:\Visual_Studio_repos\MFC\1\
*/
void CtestDlg::OnBnClickedButton1()
{
    wchar_t a1[12], a2[12], a3[12]; 

    //方法一 GetWindowText
    //GetDlgItem(IDC_EDIT_1)->GetWindowText(a1,12);
    //GetDlgItem(IDC_EDIT_2)->GetWindowText(a2, 12);
    //_itow_s(_wtoi(a1) + _wtoi(a2),a3,10);
    //SetDlgItemText(IDC_EDIT_3, a3);

    //方法二 GetDlgItemText
    //GetDlgItemText(IDC_EDIT_1,a1,12);
    //GetDlgItemText(IDC_EDIT_2, a2,12);
    //_itow(_wtoi(a1) + _wtoi(a2), a3, 10);
    //SetDlgItemText(IDC_EDIT_3, a3);

    //方法三 GetDlgItemInt
    //int a = GetDlgItemInt(IDC_EDIT_1);
    //int b = GetDlgItemInt(IDC_EDIT_2);
    //SetDlgItemText(IDC_EDIT_3, _itow(a + b, a3, 10));

    //方法四 关联控件

    //方法五 关联变量

    //方法六 SendMessage
    //::SendMessage(GetDlgItem(IDC_EDIT_1)->m_hWnd, WM_GETTEXT, (WPARAM)12, (LPARAM)a1);
    //::SendMessage(GetDlgItem(IDC_EDIT_2)->m_hWnd, WM_GETTEXT, (WPARAM)12, (LPARAM)a2);
    //::SendMessage(GetDlgItem(IDC_EDIT_3)->m_hWnd, WM_SETTEXT, (WPARAM)12, (LPARAM)(_itow(_wtoi(a1) + _wtoi(a2), a3, 10)));

    //方法七 SendDlgItemMessage，利用失败
    //::SendDlgItemMessage(GetDlgItem(IDC_EDIT_1)->m_hWnd, IDC_EDIT_1, WM_GETTEXT, (WPARAM)12, (LPARAM)a1);
    //::SendDlgItemMessage(GetDlgItem(IDC_EDIT_2)->m_hWnd, IDC_EDIT_2, WM_GETTEXT, (WPARAM)12, (LPARAM)a1);
    //::SendDlgItemMessage(GetDlgItem(IDC_EDIT_3)->m_hWnd, IDC_EDIT_3, WM_SETTEXT, (WPARAM)12,(LPARAM)(_itow(_wtoi(a1) + _wtoi(a2), a3, 10)));

}