MFC, How do I check the CString format is match the IP Format

Question

MFC, How do I check the CString format is match the IP Format,

For example User input

192.168,1,1 Error format

256.256.2.2 Error format

192.168.2 Error format

Some tip tell for me, thx

If you're trying to validate a user-entered string, you could use the [`CIPAddressCtrl`](http://msdn.microsoft.com/en-us/library/596yzwbb.aspx) instead. — Roger Rowland, May 05 '14 at 15:51

score 0 · Answer 1 · answered May 05 '14 at 10:07

0

Search the string, using Find(), Mid() or Tokenize() and validate it's contents, based on a few required rules:

e.g.

no alpha characters
precisely 3 periods (.)
numbers between periods
0 <= number <= 255
first number > 0
etc...

answered May 05 '14 at 10:07

acraig5075

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score 0 · Accepted Answer · answered May 06 '14 at 02:08

OK, I find the solution

// precisely 3 periods (.), my ip is save if strCtrlIP
    CString strCheck(strCtrlIP);
    int nPointNum = 0;

    nPointNum = strCheck.Remove('.');

    if(nPointNum != 3)
    {
        AfxMessageBox(_T("IP example：192.168.0.1"));
        return;
    }

    // numbers between periods, 0 <= number <= 255
    strCheck.Format(_T("%s"), strCtrlIP);
    while(strCheck.Find(_T(".")) >= 0)
    {
        int nLoc = strCheck.Find(_T("."));
        int nVal = _ttoi(strCheck.Left(nLoc));
        strCheck = strCheck.Right(strCheck.GetLength() - (nLoc+1)); // egnore point

        if(nVal < nUserLimitDown || nVal > nUserLimitUp || strCheck.IsEmpty())
        {
            AfxMessageBox(_T("IP example：192.168.0.1"));
            return;
        }
    }
    if(_ttoi(strCheck) < nUserLimitDown || _ttoi(strCheck) > nUserLimitUp)
    {
        AfxMessageBox(_T("IP example：192.168.0.1"));
        return;
    }

MFC, How do I check the CString format is match the IP Format

2 Answers2