How Export Data grid view using closedXML with filter applied?

Question

I have two problems. 1st problem is after filter the rows when I export to excel it gives me all data with out filter applied.

the second is how to filter using b/n two dates? ```(dgvEmployeeList.DataSource as DataTable).DefaultView.RowFilter = string.Format("date?????);

DataGridView Filter

 private void btnSearchEmployeeType_Click(object sender, EventArgs e)
        {
            string searchValue = cbSearchByEmployeeType.Text;
            try
            {
               (dgvEmployeeList.DataSource as DataTable).DefaultView.RowFilter = string.Format("EmployeeType  like '%" + searchValue + "%'");
            }
            catch (Exception exc)
            {
                MessageBox.Show(exc.Message);
            }
        }

Export DataGridView

 private void btnExportExcel_Click(object sender, EventArgs e)
        {
            using ( XLWorkbook workbook = new XLWorkbook())
              {

                workbook.Worksheets.Add((dgvEmployeeList.DataSource as DataTable), "Employees");// here is the problem 
                 workbook.SaveAs(sfd.FileName);
                 MessageBox.Show("You Have Successfully Exported your Data to an Excel File", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
              }
        }

any help! thanks

Answer 1

To set up a RowFilter with dates enclose the date value strings with # characters. To avoid problems with current culture format the dates with their ToString() to be sure the filter parser will understand it. See PoC below.

[TestMethod]
public void MyTestMethod()
{
    var dt = new DataTable();
    dt.Columns.Add(new DataColumn("dt", typeof(DateTime)));
    dt.Rows.Add(new object[] { new DateTime(1999, 01, 01) });
    dt.Rows.Add(new object[] { new DateTime(2000, 02, 01) });
    dt.Rows.Add(new object[] { new DateTime(2001, 03, 01) });
    dt.Rows.Add(new object[] { new DateTime(2002, 04, 01) });

    var startDate = new DateTime(2000, 01, 01);
    var endDate = new DateTime(2001, 01, 01);

    // use date strings between # signs and 
    // formatted via current culture to be sure it is parseable
    dt.DefaultView.RowFilter = $"dt >= #{startDate}# AND dt <= #{endDate}#";

    var r = dt.DefaultView.ToTable();
    Assert.IsTrue(r.Rows
        .Cast<DataRow>()
        .Select(i => (DateTime)i[0])
        .All(j => j >= startDate && j <= endDate));
}