参数@BranchName没有默认值

Question

I'm trying to develop inventory control system for computer department of my office. It will keep track of ins and outs of machines from branches which are send to Head Office for repair. I'll also use crystal report to display all the records from Microsoft Access 2010. I have this error message box pops up when I click on save button of entry form.

(Parameter @BranchName has no default value)

I use Microsoft Access 2010, C#.NET with VS 2010. Please help me.

    private void btnSave_Click(object sender, EventArgs e)
    {
        {
            OleDbConnection connect = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0; Data Source=C:\Users\NLA\Documents\Visual Studio 2010\Projects\GlobalTreasureBank\GlobalTreasureBank\GTBDB.accdb;Jet OLEDB:Database Password=admin@GTB");
                try
                {
                    connect.Open();
                    OleDbCommand command = new OleDbCommand();
                    command.Connection=connect;
                    command.CommandText= "INSERT INTO Machine (BranchName, MachineName, ArrivedDate, FaultDetail, ReturnDate, Remark, Technician)" + "VALUES (@BranchName, @MachineName, @ArrivedDate, @FaultDetail, @ReturnDate, @Remark, @Technician)";

                    string BranchName = txtbBranch.Text;
                    string MachineName = txtbMachine.Text;
                    string FaultDetail = rtxtbFault.Text;
                    string Remark = rtxtbRemark.Text;
                    string Technician = txtbTechnician.Text;
                    DateTime ArrivedDate = dtpArrive.Value;
                    DateTime ReturnDate = dtpReturn.Value;

                    command.Parameters.Add("ArrivedDate", OleDbType.Date);
                    command.Parameters.Add("ReturnDate", OleDbType.Date);

                    command.Parameters.AddWithValue("@BranchName", txtbBranch.Text);
                    command.Parameters.AddWithValue("@MachineName", txtbMachine.Text);
                    command.Parameters.AddWithValue("@FaultDetail", rtxtbFault.Text);
                    command.Parameters.AddWithValue("@Remark", rtxtbRemark.Text);
                    command.Parameters.AddWithValue("@Technician", txtbTechnician.Text);
                    command.Parameters.AddWithValue("@ArrivedDate", dtpArrive.Value);
                    command.Parameters.AddWithValue("@ReturnDate", dtpReturn.Value);

                    command.ExecuteNonQuery();
                    MessageBox.Show ("Successfully write to database", "Write to Database", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    connect.Close();
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message);
                    connect.Close();
                }
            }
        }
    }
}

Answer 1

Note 1 : OleDB doesnot accept the named parameters .
Note 2 : OleDB Parameters need tobe in sequential order.

Try This:

command.CommandText= "INSERT INTO Machine (BranchName, MachineName, ArrivedDate, 
   FaultDetail, ReturnDate, Remark, Technician) VALUES (?,?,?,?,?,?,?)";


command.Parameters.AddWithValue("@BranchName", txtbBranch.Text);
command.Parameters.AddWithValue("@MachineName", txtbMachine.Text);
command.Parameters.AddWithValue("@ArrivedDate", dtpArrive.Value);
command.Parameters.AddWithValue("@FaultDetail", rtxtbFault.Text);
command.Parameters.AddWithValue("@ReturnDate", dtpReturn.Value);
command.Parameters.AddWithValue("@Remark", rtxtbRemark.Text);
command.Parameters.AddWithValue("@Technician", txtbTechnician.Text);