private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
dtpFrom.Text = Convert.ToDateTime(GlbData.getFirstDate(cboDateRange)).ToShortDateString();
dtpTo.Text = Convert.ToDateTime(GlbData.getLastDate(cboDateRange, Convert.ToDateTime(dtpFrom.Text))).ToShortDateString();
}