void BindDeposits()
    {
        if (txtdate.Text == "")
        {
            txtdate.Text = "1/1/1900";
        }
        if (txtrefno.Text == "")
        {
            txtrefno.Text = "1/1/1900";
        }

        FlightBAL obj = new FlightBAL();
        obj.FromDate = Convert.ToDateTime(txtdate.Text);
        obj.ToDate = Convert.ToDateTime(txtrefno.Text);
        obj.agentId = Convert.ToInt32(Session["UserId"]);
        DataSet ds = obj.GetFlightSalesReport();
        if (ds != null)
        {
            if (ds.Tables.Count > 0)
            {
                if (ds.Tables[0].Rows.Count > 0)
                {
                    gvDeposits.DataSource = ds;
                    gvDeposits.DataBind();
                    ViewState["gv"] = ds;
                    trpaging.Visible = true;
                    lblerrormsg.Visible = false;
                    gvDeposits.Visible = true;
                }
                else
                {
                    trpaging.Visible = false;
                    lblerrormsg.Text = "No Data Found";
                    lblerrormsg.ForeColor = System.Drawing.Color.Red;
                    lblerrormsg.Visible = true;
                    gvDeposits.Visible = false;
                }
            }
            else
            {
                trpaging.Visible = false;
                lblerrormsg.Text = "No Data Found";
                lblerrormsg.ForeColor = System.Drawing.Color.Red;
                lblerrormsg.Visible = true;
                gvDeposits.Visible = false;
            }
        }
        else
        {
            trpaging.Visible = false;
            lblerrormsg.Text = "No Data Found";
            lblerrormsg.ForeColor = System.Drawing.Color.Red;
            lblerrormsg.Visible = true;
            gvDeposits.Visible = false;
        }
        if (txtdate.Text == "1/1/1900")
        {
            txtdate.Text = "";
        }
        if (txtrefno.Text == "1/1/1900")
        {
            txtrefno.Text = "";
        }
    }
    protected void gvDeposits_Sorting(object sender, GridViewSortEventArgs e)
    {
        try
        {
            try
            {
                string strExpression = e.SortExpression;
                string strDirection = ViewState["SortDirection"].ToString();
                FlightBAL objBal = new FlightBAL();

                if (txtdate.Text == "")
                {
                    txtdate.Text = "1/1/1900";
                }
                if (txtrefno.Text == "")
                {
                    txtrefno.Text = "1/1/1900";
                }
                objBal.FromDate = Convert.ToDateTime(txtdate.Text);
                objBal.ToDate = Convert.ToDateTime(txtrefno.Text);
                DataSet ds = objBal.GetFlightSalesReport();
                DataTable dt = ds.Tables[0];
                DataView dv = new DataView(dt);
                dv.Sort = strExpression + strDirection;
                gvDeposits.DataSource = dv;
                gvDeposits.DataBind();
                if (strDirection == " ASC") { ViewState["SortDirection"] = " DESC"; } else { ViewState["SortDirection"] = " ASC"; }

                if (txtdate.Text == "1/1/1900")
                {
                    txtdate.Text = "";
                }
                if (txtrefno.Text == "1/1/1900")
                {
                    txtrefno.Text = "";
                }

            }
            catch (Exception ex)
            {
                lblMsg.InnerHtml = ex.Message;
                throw;
            }
        }
        catch (Exception ex)
        {
            lblMsg.InnerHtml = ex.Message;
            throw;
        }
    }