如何在Windows窗体应用程序中缓存DataGridView

Question

I am working on an application in which data is retrieved from four SQL tables using joins and the retrieved data is populated to a datagridview on a windows form. I have two Radio Buttons ALL and DrawDate , by default ALL Radio Button is selected and once the application is opened it populates all the data on to the datagridview and when I select DrawDate Radio Button , only the data related to that draw date is populated on the datagridview . Everything looks fine until then but after selecting DrawDate Radio Button and if a user want to get all the data again by selecting ALL Radio Button , it again loads all data from the database server which is not preferred. Is there any better way I can cache the data populated once the application is opened and populate it when a user selects ALL Radio Button later when he needs it?

C# Code

sqlcon = GetConnectionString();
            try
            {
                sqlcon.Open();

                //var sw = Stopwatch.StartNew();

                for (int i = 0; i < dgvPaymentsReceived_Collections.RowCount; i++)
                {
                    int trademonth = Convert.ToInt32(dgvPaymentsReceived_Collections.Rows[i].HeaderCell.Value);


                    for (int j = 0; j < dgvPaymentsReceived_Collections.ColumnCount; j++)
                    {
                        int paymentmonth = Convert.ToInt32(dgvPaymentsReceived_Collections.Columns[j].HeaderCell.Value);

                        //var sw = Stopwatch.StartNew();

                        SqlCommand cmd_PaymentsReceived = new SqlCommand();

                        cmd_PaymentsReceived.Connection = sqlcon;
                        cmd_PaymentsReceived.CommandType = CommandType.StoredProcedure;
                        cmd_PaymentsReceived.CommandText = sp_PaymentsReceved_Collections;

                        cmd_PaymentsReceived.Parameters.Add(new SqlParameter("@trademonth", trademonth));
                        cmd_PaymentsReceived.Parameters.Add(new SqlParameter("@paymentmonth", paymentmonth));


                        SqlDataAdapter da_PaymentsReceived_Collections = new SqlDataAdapter();
                        DataTable dt_PaymentsReceived_Colletions = new DataTable();

                        da_PaymentsReceived_Collections.SelectCommand = cmd_PaymentsReceived;
                        da_PaymentsReceived_Collections.Fill(dt_PaymentsReceived_Colletions);

                        //sw.Stop();
                        //MessageBox.Show(sw.ElapsedMilliseconds.ToString());

                        dgvPaymentsReceived_Collections.Rows[i].Cells[j].Value = dt_PaymentsReceived_Colletions.Rows[0][0].ToString();

                    }
                }

                sqlcon.Close();
            }

Answer 1

You haven't shown us any code. What kind of connection did you use? Don't bind your database source to a datagridview - use either an Enumerable / IList collection or DataSet as your data holder and then assign only the part of it (filtering it with LINQ) to your datagridview. This way you don't have to create a new collection every time in memory, just iterate over the items with given condition.

Answer 2

假设您没有大量的数据，则可以将SQL结果存储在DataTable中，然后将其绑定到DataGridView

Answer 3

单击“ All按钮时，您可以考虑将SQL数据存储在IEnumerable数据结构中，并将该集合绑定到gridview，然后在DrawDate按钮单击期间，对集合进行适当排序。

Answer 4

You can hang on to your original data table and create a separate DataTable to bind to your DataGridView if you want to be able to change what is displayed.

Just fill your data table once, and then create a new DataTable to hide what you don't need.

This might use slightly more memory depending on the size of your DataTable, but it's probably the easiest solution to implement.

    DataTable viewedData = dt_PaymentsReceived_Colletions;

    if(hideIncome.Checked) {
        viewedData.Columns.Remove("Income");
        viewedData.AcceptChanges();
    }

    DataGridView1.DataSource = viewedData;