Custom Pagging and Sorting in GridView

//Posted By Suresh


//HTML Code
<br /><div style="overflow: auto; height: 280px; width: 680px"><br /> <asp:GridView ID="GVBooking" runat="server" BackColor="#FBDAA0" Width="1200px" AutoGenerateColumns="true" BorderColor="Black" BorderWidth="1px" CellPadding="0" Font-Names="Arial" BorderStyle="Solid" ForeColor="Black" Font-Size="9pt" OnRowCreated="GVBooking_RowCreated" EmptyDataText="Data Not Available" AllowPaging="True" PageSize="15" OnPageIndexChanging="GVBooking_PageIndexChanging" Font-Strikeout="False" OnDataBound="GVBooking_DataBound" OnSorting = "GVBooking_Sorting" AllowSorting="true"><br /> <PagerTemplate><br /> <asp:ImageButton ID="ImgbtnFirst" runat="server" ImageUrl="~/Images/first.png" CommandArgument="First" CommandName="Page" OnCommand="Paginate" Height="18px" ToolTip="First" /><br /> <asp:ImageButton ID="ImgbtnPrev" runat="server" ImageUrl="~/Images/previous.png" CommandArgument="Prev" CommandName="Page" OnCommand="Paginate" Height="18px" ToolTip="Previous" /><br /> Page<br /> <asp:DropDownList OnSelectedIndexChanged="ddlPages_SelectedIndexChanged" ID="ddlPages"<br /> runat="server" AutoPostBack="True"><br /> </asp:DropDownList><br /> of<br /> <asp:Label Height="18px" ID="lblPageCount" ToolTip="Total Pages" runat="server"></asp:Label><br /> <asp:ImageButton ID="ImgbtnNext" runat="server" ImageUrl="~/Images/next.png" CommandArgument="Next"<br /> CommandName="Page" OnCommand="Paginate" Height="18px" ToolTip="Next" /><br /> <asp:ImageButton ID="ImgbtnLast" runat="server" ImageUrl="~/Images/last.png" CommandArgument="Last"<br /> CommandName="Page" OnCommand="Paginate" Height="18px" ToolTip="Last" /><br /> </PagerTemplate><br /> <PagerStyle CssClass="GridPager" BackColor="#CC3300" Font-Bold="True" ForeColor="White"<br /> VerticalAlign="Middle" Height="18px" HorizontalAlign="Left" /><br /> <HeaderStyle CssClass="GridHeader"></HeaderStyle><br /> <AlternatingRowStyle CssClass="GridAltItem" /><br /> <PagerSettings Position="Top" /><br /> <RowStyle CssClass="GridItem" /><br /> </asp:GridView><br /> </div><br />
//Code Behind Code

private const string ASCENDING = " ASC";
private const string DESCENDING = " DESC";
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
pupulategrid();
}
}

protected void GVBooking_PageIndexChanging(object sender, GridViewPageEventArgs e)
{
GVBooking.PageIndex = e.NewPageIndex;
pupulategrid();

}

protected void GVBooking_RowCreated(object sender, GridViewRowEventArgs e)
{
// Leave header and footer of Gridview and assign in the rest of the item row
if (e.Row.RowType != DataControlRowType.Header || e.Row.RowType != DataControlRowType.Header)
{
e.Row.Attributes.Add("onmouseout", "this.className='normalRow'");
e.Row.Attributes.Add("onmouseover", "this.className='highlightRow'");
}
}

protected void GVBooking_DataBound(Object sender, EventArgs e)
{
GridViewRow gvrPager = GVBooking.TopPagerRow;
if (gvrPager == null) return;
// get your controls from the gridview
DropDownList ddlPages = (DropDownList)gvrPager.Cells[0].FindControl("ddlPages");
Label lblPageCount = (Label)gvrPager.Cells[0].FindControl("lblPageCount");
if (ddlPages != null)
{
// populate pager
for (int i = 0; i < GVBooking.PageCount; i++)
{
int intPageNumber = i + 1;
System.Web.UI.WebControls.ListItem lstItem = new System.Web.UI.WebControls.ListItem(intPageNumber.ToString());
if (i == GVBooking.PageIndex)
lstItem.Selected = true;
ddlPages.Items.Add(lstItem);
}
}
// populate page count
if (lblPageCount != null)
lblPageCount.Text = GVBooking.PageCount.ToString();
}

protected void ddlPages_SelectedIndexChanged(Object sender, EventArgs e)
{
GridViewRow gvrPager = GVBooking.TopPagerRow;
DropDownList ddlPages = (DropDownList)gvrPager.Cells[0].FindControl("ddlPages");
GVBooking.PageIndex = ddlPages.SelectedIndex;
// a method to populate your grid
pupulategrid();
}

protected void Paginate(object sender, CommandEventArgs e)
{
// get the current page selected
int intCurIndex = GVBooking.PageIndex;
switch (e.CommandArgument.ToString().ToLower())
{
case "first":
GVBooking.PageIndex = 0;
break;
case "prev":
if (GVBooking.PageIndex > 0)
GVBooking.PageIndex = intCurIndex - 1;
break;
case "next":
int i = GVBooking.PageIndex + 1;
if (i <= GVBooking.PageCount)
{
GVBooking.PageIndex = i;
}
break;
case "last":
GVBooking.PageIndex = GVBooking.PageCount;
break;
}
// popultate the gridview control
pupulategrid();
}

public void pupulategrid()
{
//Grid Filling From Data base
//Bind Grid
// Also Maintain Session Of Data table
//Session["DataTableTotalBooking"]=Dt
}




public SortDirection GridViewSortDirection
{
get
{
if (ViewState["sortDirection"] == null)
ViewState["sortDirection"] = SortDirection.Ascending;

return (SortDirection)ViewState["sortDirection"];
}
set { ViewState["sortDirection"] = value; }
}

protected void GVBooking_Sorting(object sender, GridViewSortEventArgs e)
{
string sortExpression = e.SortExpression;

if (GridViewSortDirection == SortDirection.Ascending)
{
GridViewSortDirection = SortDirection.Descending;
SortGridView(sortExpression, DESCENDING);
}
else
{
GridViewSortDirection = SortDirection.Ascending;
SortGridView(sortExpression, ASCENDING);
}

}

private void SortGridView(string sortExpression, string direction)
{

DataTable dt = (DataTable)Session["DataTableTotalBooking"];

DataView dv = new DataView(dt);
dv.Sort = sortExpression + direction;
GVBooking.DataSource = dv;
GVBooking.DataBind();
}