Clear DataGridView datasource linked to Entity Framework

Question

I'm new to Entity Framework, I have a DataGridView connected to Entity Framework as it shown below

dgvDebit.DataSource = (from daily in accountingEntities.DailyAccounts
                       join voucherdetails in accountingEntities.VoucherDetails on daily.DailyId equals voucherdetails.DailyId
                       where voucherdetails.VoucherId == keyvalue
                       group voucherdetails by daily.DailyName into dgroup
                       select new
                              {
                                  DailyName = dgroup.Key,
                                  SumOfDebit = dgroup.Sum(s => s.Debit)
                              }).ToList();

My question is: I want to clear DataGridView datasource but every thing I did has failed - please any help here?

Answer 1

OK, so you want to bind to an empty list of the type that you have.

Step 1: define a .NET type for your query result return type:

public class ResultDTO
{
    public string DailyName { get; set; }
    public decimal SumOfDebit { get; set; }
}

Step 2: change your "normal" query to:

dgvDebit.DataSource = (from daily in accountingEntities.DailyAccounts
                       join voucherdetails in accountingEntities.VoucherDetails on daily.DailyId equals voucherdetails.DailyId
                       where voucherdetails.VoucherId == keyvalue
                       group voucherdetails by daily.DailyName into dgroup
                       select new ResultDTO
                              {
                                  DailyName = dgroup.Key,
                                  SumOfDebit = dgroup.Sum(s => s.Debit)
                              }).ToList();

Step 3: if you want to "clear" the DataGridView, but retain the columns, you can now use:

dgvDebit.DataSource = new List<ResultDTO>();