I am working on implementing a scientific calculator in MFC, C++.

I have implemented most of the functionality of a scientific calculator, except for the parentheses feature.

In fact, when I type the parentheses button, the parentheses are entered in the input window.

Once I type 5+5 without parentheses, I get 10.

However, when I put a number inside the parentheses, the number is treated as a zero. For example, I get (5)+5= 5.

I’ve spent a lot of time thinking about it, Googling, and asking GPT, but I can’t get an answer.

Please let me know if I missed or doing wrong anything, thanks.

My code :

 ** void CMFCApplication20Dlg::OnBnClickedButtonLeftParen()** 
{
    CString temp;
    GetDlgItem(IDC_STATIC_VIEW)->GetWindowText(temp);
    temp += _T("("); // 왼쪽 괄호 추가
    SetDlgItemText(IDC_STATIC_VIEW, temp);
    m_LeftParenCount++;
} 

** void CMFCApplication20Dlg::OnBnClickedButtonRightParen()** 
{
    CString temp;
    GetDlgItem(IDC_STATIC_VIEW)->GetWindowText(temp);
    if (m_LeftParenCount > m_RightParenCount)
    {
        temp += _T(")"); // 오른쪽 괄호 추가
        SetDlgItemText(IDC_STATIC_VIEW, temp);
        m_RightParenCount++;
    }
    else
    {
        AfxMessageBox(_T("Cannot add right parenthesis. Mismatched parentheses."));
    }
} 

 ** void CMFCApplication20Dlg::OnBnClickedButtonEquals()** 
{
    CString temp;
    GetDlgItem(IDC_STATIC_VIEW)->GetWindowText(temp);
    m_LeftParenCount = 0;
    m_RightParenCount = 0;
    AfterData = _ttof(temp); // 지수값(추가함)

    // CString을 double로 변환 (소수점 지원)
    double result = 0.0;
    double beforeData = _ttof(ViewStrData); // ViewStrData를 CString에서 double로 변환
    double afterData = _ttof(temp); // temp를 CString에서 double로 변환

    // % 코드임 
    int percentPos = temp.Find(_T("%"));
    if (percentPos != -1)
    {
        // `%` 기호가 있을 경우, 해당 기호를 기준으로 문자열 분리
        CString numberStr = temp.Left(percentPos); // '%' 기호 이전 부분
        double number = _ttof(numberStr); // 문자열을 double로 변환
        double result = number / 100.0;

        // 결과를 문자열로 변환하고 IDC_STATIC_VIEW에 표시
        CString resultStr;
        resultStr.Format(_T("%.2f"), result);
        SetDlgItemText(IDC_STATIC_RESULT, resultStr);
        ChangeCheck = true;
        Sign = 0;
        return;
    }

    // 계산 로직
    switch (Sign)
    {
        case 1: result = beforeData + afterData; break;
        case 2: result = beforeData - afterData; break;
        case 3: result = beforeData * afterData; break;
        case 4: 
            if (afterData != 0.0)
                result = beforeData / afterData;
            else
            {
                AfxMessageBox(_T("Zero division error!"));
                return;
            }
            break;
        case 5: 
            if (afterData != 0.0)
                result = fmod(beforeData, afterData);
            else
                AfxMessageBox(_T("Zero division error!"));
            break;
        // 추가적인 연산자 처리...
        default: AfxMessageBox(_T("Invalid operation!")); return;
    } 

    // 결과를 결과 창에 표시
    UpdateResultView(result);
    GetDlgItem(IDC_STATIC_VIEW)->SetWindowText(_T(""));
    ChangeCheck = true;
    Sign = 0;
}