Source code for New user in CCFD - 3

protected void btnSubmit_Click(object sender, EventArgs e)

    {              

        //To Sum The Total Amount made By the Card Holder

        data.DBCmdOpen("select sum(amount) from account where cardNo='" + txtCardNo.Text + "'");

        data.dr = data.cmd.ExecuteReader();

        if (data.dr.HasRows)

        {

            data.dr.Read();

            if (data.dr[0].ToString() == "")

            {

                sumAmount = 0;

            }

            else

            {

                sumAmount = Convert.ToInt32(data.dr[0].ToString());

            }

        }

        data.DBReaderClose();

        //To Find Whether the CreditLimit is Exceed

        data.DBCmdOpen("select * from card where cardNo='" + txtCardNo.Text + "'");

        data.dr = data.cmd.ExecuteReader();

        if (data.dr.HasRows)

        {

            data.dr.Read();

            CreditLimit = Convert.ToInt32(data.dr["CreditLimit"].ToString());

        }

        data.DBReaderClose();

        // To Verify Genuine User Or Not

        data.DBCmdOpen("select count(cardNo) from account where cardNo='" + txtCardNo.Text + "'");

        data.dr = data.cmd.ExecuteReader();

        if (data.dr.HasRows)

        {

            data.dr.Read();

            if (data.dr[0].ToString() == "")

            {

                insertData();

            }

            else

            {

                int count = Convert.ToInt32(data.dr[0].ToString());

                data.DBReaderClose();

                if (count <= 3)

                {

                    insertData();

                }

                else

                {

                    int tranAmt = Convert.ToInt32(txtAmt.Text);

                    string trnPlace = txtPalce.Text;