how to filter datagrid data from date to date in wpf C#

Question

I can't filter datagrid data from date to date in wpf C# .

Here is my code:

public partial class MainWindow : Window
{
    public DateTime SelectedDate1;
    public DateTime SelectedDate2;
    SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=GOLGOHAR_DB;Integrated Security=True");

    GOLGOHAR_DBEntities GOG = new GOLGOHAR_DBEntities();
    public MainWindow()
    {
        InitializeComponent();
        loadgrid();
         datetimepicker1.SelectedDate = DateTime.Now.Date;
         datetimepicker2.SelectedDate = DateTime.Now.Date;
    }


    private void loadgrid()
    {
        var data = from r in GOG.QC_Bentonite_Phy_Tables select r;
        dataGrid.ItemsSource = data.ToList();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        DateTime datetime = (dataGrid.SelectedItem as QC_Bentonite_Phy_Tables).DateTime;
        QC_Bentonite_Phy_Tables ben_phy = (from r in GOG.QC_Bentonite_Phy_Tables where r.DateTime == datetime select r).SingleOrDefault();
        GOG.QC_Bentonite_Phy_Tables.Remove(ben_phy);
        GOG.SaveChanges();
        dataGrid.ItemsSource = GOG.QC_Bentonite_Phy_Tables.ToList();
    }

    private void FetchData_Click(object sender, RoutedEventArgs e)
    {
        SelectedDate1 = datetimepicker1.SelectedDate.Value;
        SelectedDate2 = datetimepicker1.SelectedDate.Value;
        SqlDataAdapter sdf = new SqlDataAdapter("select * from QC_Bentonite_Phy_Tables where DATED between '" + SelectedDate1.ToString() + "' and '" + SelectedDate2.ToString() + "'", con);
        DataSet ds = new DataSet();
        con.Open();
        sdf.Fill(ds);
        con.Close();
        dataGrid.ItemsSource = GOG.QC_Bentonite_Phy_Tables.ToList();

    }
}

please can someone help me? I am using this method to filter data in datagrid

private void FetchData_Click(object sender, RoutedEventArgs e)
        {
            SelectedDate1 = datetimepicker1.SelectedDate.Value;
            SelectedDate2 = datetimepicker1.SelectedDate.Value;
            SqlDataAdapter sdf = new SqlDataAdapter("select * from QC_Bentonite_Phy_Tables where DATED between '" + SelectedDate1.ToString() + "' and '" + SelectedDate2.ToString() + "'", con);
            DataSet ds = new DataSet();
            con.Open();
            sdf.Fill(ds);
            con.Close();
            dataGrid.ItemsSource = GOG.QC_Bentonite_Phy_Tables.ToList();

        }

Answer 1

试试下面

SqlDataAdapter sdf = new SqlDataAdapter("select * from QC_Bentonite_Phy_Tables where DATED between '" + SelectedDate1+ "' and '" + SelectedDate2+"'",con);