int num1,num2,num3;
CString ch1,ch2,ch3;
GetDlgItem(IDC_EDIT1)->GetWindowTextW(ch1);
GetDlgItem(IDC_EDIT2)->GetWindowTextW(ch2);
num1=(int)_ttoi(ch1);
num2=(int)_ttoi(ch2);
num3=num1+num2;
//_itow(num3,ch3,10);
ch3.Format(_T("%d"), num3);
GetDlgItem(IDC_EDIT3)->SetWindowTextW(ch3);