private void ButtonNineBtn_Click(object sender, EventArgs e)
        {
            var _qFunSS = TextBoxQFATxb.SelectionStart;

            //_valueString = ValueToAbsTxb.Text;
            //_isComma = _valueString.Contains(CommaSymbol);
            if (Checked._checkedTextBoxQFA == true)
            {
                TextBoxQFATxb.Focus();
                TextBoxQFATxb.Text = TextBoxQFATxb.Text.Insert(_qFunSS, "9");
                _qFunSS++;
                // _a += Convert.ToDouble(TextBoxQFATxb.Text);
                TextBoxQFATxb.SelectionStart = _qFunSS;
                _charChecker.IsCommaCheckerQFAMethod();
                _charChecker.IsMinusCheckerQFAMethod();

                // _charChecker.IsCommaCheckerFunLinAMethod();
                // _charChecker.IsMinusCheckerFunLinAMethod();
                // _charChecker.IsMinusCheckerMethod();
            }
            var _qFunSSB = TextBoxQFBTxb.SelectionStart;

            if (Checked._checkedTextBoxQFB == true)
            {
                TextBoxQFBTxb.Focus();
                TextBoxQFBTxb.Text = TextBoxQFBTxb.Text.Insert(_qFunSSB, "9");
                _qFunSSB++;
                //  _b += Convert.ToDouble(TextBoxQFBTxb.Text);
                TextBoxQFBTxb.SelectionStart = _qFunSSB;
                _charChecker.IsCommaCheckerQFBMethod();
                _charChecker.IsMinusCheckerQFBMethod();
                //_charChecker.IsCommaCheckerFunLinBMethod();
                // _charChecker.IsMinusCheckerFunLinBMethod();
            }
            var _qFunSSC = TextBoxQFCTxb.SelectionStart;

            if (Checked._checkedTextBoxQFC == true)
            {
                TextBoxQFCTxb.Focus();
                TextBoxQFCTxb.Text = TextBoxQFCTxb.Text.Insert(_qFunSSC, "9");
                _qFunSSC++;
                TextBoxQFCTxb.SelectionStart = _qFunSSC;
                _charChecker.IsCommaCheckerQFCMethod();
                _charChecker.IsMinusCheckerQFCMethod();
            }
        }
        private void ButtonNineBtn_Click(object sender, EventArgs e)
        {
            var _qFunSS = TextBoxQFATxb.SelectionStart;


            if (Checked._checkedTextBoxQFA == true)
            {
                TextBoxQFATxb.Focus();
                TextBoxQFATxb.Text = TextBoxQFATxb.Text.Insert(_qFunSS, "9");
                _qFunSS++;

                TextBoxQFATxb.SelectionStart = _qFunSS;
                _charChecker.IsCommaCheckerQFAMethod();
                _charChecker.IsMinusCheckerQFAMethod();
            }
            var _qFunSSB = TextBoxQFBTxb.SelectionStart;

            if (Checked._checkedTextBoxQFB == true)
            {
                TextBoxQFBTxb.Focus();
                TextBoxQFBTxb.Text = TextBoxQFBTxb.Text.Insert(_qFunSSB, "9");
                _qFunSSB++;

                TextBoxQFBTxb.SelectionStart = _qFunSSB;
                _charChecker.IsCommaCheckerQFBMethod();
                _charChecker.IsMinusCheckerQFBMethod();
            }
            var _qFunSSC = TextBoxQFCTxb.SelectionStart;

            if (Checked._checkedTextBoxQFC == true)
            {
                TextBoxQFCTxb.Focus();
                TextBoxQFCTxb.Text = TextBoxQFCTxb.Text.Insert(_qFunSSC, "9");
                _qFunSSC++;
                TextBoxQFCTxb.SelectionStart = _qFunSSC;
                _charChecker.IsCommaCheckerQFCMethod();
                _charChecker.IsMinusCheckerQFCMethod();
            }
        }