private void txtBear_TextChanged(object sender, EventArgs e) { if (txtBear.Text.Trim() == "") { bf.sfs.BearManual = -1; bf.sfs.BearErr = 0; bf.HAFLErr = bf.sfs.BearErr; lblBearErr.Text = "0"; } else { bf.sfs.BearManual = CommonStr.ConvertDMSToDec(txtBear.Text); bf.sfs.BearErr = CalcClass.CalcAngErr(bf.sfs.Bear, bf.sfs.BearManual); bf.HAFLErr = bf.sfs.BearErr; lblBearErr.Text = CommonStr.ConvertDecToDMS(bf.sfs.BearErr); } }