protected void DtgGestiones_SelectedIndexChanged(object sender, EventArgs e)
        {

            if (this.IsPostBack)
            {
                try
                {
                    DtTab = new DataTable();
                    DtTab = (DataTable)Session["Data"];
                    DtgGestiones.CurrentPageIndex = 0;
                    DtgGestiones.CurrentPageIndex = e.NewPageIndex;
                    DtgGestiones.DataSource = DtTab;
                    DtgGestiones.DataBind();

                    //LLenarGrilla();
                }
                catch (Exception Ex)
                {


                }
            }
        }

<asp:DataGrid ID="DtgGestiones" runat="server" AllowPaging="true" AllowSorting="true" AutoGenerateColumns="false"
                        BorderWidth="1px" CellPadding="0" CellSpacing="0" Font-Bold="False" Font-Overline="False" Font-Strikeout="False"
                        HorizontalAlign="Left" PageSize="250" PagerStyle-Mode="NumericPages" HeaderStyle-Font-Bold="true"
                        CssClass="table table-hover table-bordered table-condensed table-striped"
                        Font-Names="Calibri" Font-Size="12px" OnItemCommand="DtgGestiones_ItemCommand" PagerStyle-CssClass="pagGrig" OnPageIndexChanged="DtgGestiones_PageIndexChanged" OnSortCommand="DtgGestiones_SortCommand" OnSelectedIndexChanged="DtgGestiones_SelectedIndexChanged">

                        <Columns>
                            <asp:BoundColumn DataField="RUBRO" SortExpression="RUBRO" HeaderText="RUBRO" ReadOnly="True">

                            </asp:BoundColumn>
                            <asp:BoundColumn DataField="OFICINA" SortExpression="OFICINA" HeaderText="OFICINA" ReadOnly="true"></asp:BoundColumn>
                            <asp:BoundColumn DataField="USUARIO ATENCION" SortExpression="USUARIO ATENCION" HeaderText="USUARIO ATENCION" ReadOnly="True"></asp:BoundColumn>
                            <asp:BoundColumn DataField="FECHA DE EMISION"  SortExpression="FECHA DE EMISION" HeaderText="FECHA DE EMISION" ReadOnly="True" DataFormatString="{0:dd/MM/yyyy}"></asp:BoundColumn>
                            <asp:BoundColumn DataField="FECHA DE VENCIMIENTO" SortExpression="FECHA DE VENCIMIENTO" HeaderText="FECHA DE VENCIMIENTO" ReadOnly="True" DataFormatString="{0:dd/MM/yyyy}">
                                <ItemStyle HorizontalAlign="Right" />
                            </asp:BoundColumn>
                            <asp:BoundColumn DataField="MONTO PAGADO" SortExpression="MONTO PAGADO" HeaderText="MONTO PAGADO" ReadOnly="True" DataFormatString="{0:0,0.00}">
                                <ItemStyle HorizontalAlign="Right" />
                            </asp:BoundColumn>
                            <asp:BoundColumn DataField="NUMERO DE RECIBO" SortExpression="NUMERO DE RECIBO" HeaderText="NUMERO DE RECIBO" ReadOnly="True" >
                                <ItemStyle HorizontalAlign="Right" />
                            </asp:BoundColumn>
                            <asp:BoundColumn DataField="PAGADO" SortExpression="PAGADO" HeaderText="PAGADO" ReadOnly="True" >
                                <ItemStyle HorizontalAlign="Right" />
                            </asp:BoundColumn>
                            <asp:BoundColumn DataField="VALIDADO" HeaderText="VALIDADO" ReadOnly="True" sortExpression="VALIDADO" >
                                <ItemStyle HorizontalAlign="Right" />
                            </asp:BoundColumn>
                            <asp:ButtonColumn CommandName="Gestiones" HeaderText="Gestionar" Text="Ver" >
                                <ItemStyle
                                    Font-Bold="False" Font-Italic="False" Font-Overline="False"
                                    Font-Strikeout="False" Font-Underline="False" HorizontalAlign="Center" />
                            </asp:ButtonColumn>
                        </Columns>
                    </asp:DataGrid>