從字串中簡單取出DomainName

diddom

{
    string FromStr;
    CString csFromStr;

    m_textBoxFrom.SetWindowText("123456@yahoo.com");

    '要取出TextBox的字串,以CWnd::GetDlgItemText最为方便,但它第二个参数型别是CString  
    CWnd::GetDlgItemText(IDC_textBoxFrom, csFromStr);

    FromStr = csFromStr.GetBuffer(0); // CString to std::string

    EmailSend *mailsender = new EmailSend;
    string str = mailsender->GetDomainName(FromStr);
}

string EmailSend::GetDomainName(string emailAddress)
{
        int atIndex = emailAddress.find("@");

        if (atIndex == -1)
        {
                return NULL;
        }
            
        return emailAddress.substr(atIndex + 1);
}