获取“字符串或二进制数据将被截断”错误，不确定为什么

Question

将Visual Studio 2017与SQL Server 2016 Express一起使用，并使用以下方法：

protected void subFinish_Click(object sender, EventArgs e)
{
    String regPattern = "^\\d{3}-\\d{8}$";
    String regPattern2 = "^\\d{11}$";


    if (Regex.IsMatch(txtAwbNum.Text, regPattern) || Regex.IsMatch(txtAwbNum.Text, regPattern2))
    {
        String AwbNum = txtAwbNum.Text;
        int doorNum = Convert.ToInt16(ddlDoorNum.SelectedValue);
        String driverName = txtDriverName.Text;
        String carrier = txtCarrier.Text;
        int pieces = Convert.ToInt32(txtPieces.Text);
        SqlDecimal GrossWt = SqlDecimal.Parse(txtGrossWt.Text);
        SqlDecimal ChargeWt = SqlDecimal.Parse(txtChargeableWt.Text);
        String flightNum = ddlFlightNum.ToString();
        SqlDateTime date = Convert.ToDateTime(txtDate.Text);
        String destination = txtDestination.Text;
        String shipper = txtShipper.Text;
        Boolean dgCheck = chkDgCheck.Checked;
        DateTime today = DateTime.Today;
        String dropoffId = DateTime.Today.ToString();


        String queryString = "INSERT INTO ExpAwbs (idExpAwbs, Pieces, GrossWt, ChargeWt, Flight, FlightDate, Shipper, Destination, dgCheck) values (@AwbNum, @pieces, @GrossWt, @ChargeWt, @flightNum, @date, @shipper, @destination, @dgCheck);";
        String queryString2 = "INSERT INTO Dropoff (idDropoff, DoorNum, Carrier, DriverName, datetime) values (@dropoffID, @doorNum, @carrier, @driverName, @today);";

        String connectionString = "Data Source=PCNAME\\SQLEXPRESS;Initial Catalog=TASdb;Integrated Security=True";

        SqlConnection connection = new SqlConnection(connectionString);
        SqlCommand command = new SqlCommand(queryString, connection);
        SqlCommand command2 = new SqlCommand(queryString2, connection);
        command.Parameters.AddWithValue("@AwbNum", AwbNum);
        command.Parameters.AddWithValue("@pieces", pieces);
        command.Parameters.AddWithValue("@GrossWt", GrossWt);
        command.Parameters.AddWithValue("@ChargeWt", ChargeWt);
        command.Parameters.AddWithValue("@flightNum", flightNum);
        command.Parameters.AddWithValue("@date", date);
        command.Parameters.AddWithValue("@destination", destination);
        command.Parameters.AddWithValue("@shipper", shipper);
        command.Parameters.AddWithValue("@dgCheck", dgCheck);
        command2.Parameters.AddWithValue("@doorNum", doorNum);
        command2.Parameters.AddWithValue("@carrier", carrier);
        command2.Parameters.AddWithValue("@driverName", driverName);
        command2.Parameters.AddWithValue("@dropoffId", dropoffId);

        command.Connection.Open();
        command.ExecuteReader();
        command.Connection.Close();

        command2.Connection.Open();
        command2.ExecuteScalar();
        command2.Connection.Close();
    }
    else
    {
        MessageBox.Show(this, "Invalid AWB. Please check again and re-submit.");
    }

}

当我运行它时，我得到一个“字符串或二进制数据将被截断。语句已被终止。”我不明白为什么会这样。我确保所有字段都小于或等于数据库中分配的大小。我唯一质疑的是GrossWt和ChargeWt，因为在数据库中他们的数据类型是Decimal（6,1），但我不认为这是问题，因为我尝试将它们取出来，并没有改变任何东西。下面是相关表的数据库表设计（FlightDate列实际上已更新为datetime数据类型）：