private void guna2DateTimePicker1_ValueChanged(object sender, EventArgs e) { int day, month, year; day = guna2DateTimePicker1.Value.Day; month = guna2DateTimePicker1.Value.Month; year = guna2DateTimePicker1.Value.Year; gvHoaDon.DataSource = dataHD.FillChitietHD_date(day, month, year); }