custom paging in a gridview

step1: custom paging in a grid view is achived by using the stored procedure described below. This procedure will retrieve records based on the pageSize and pageIndex.
pageSize is the number of records to be displayed in a page and pageIndex is the current pagenumber.

alter procedure pro_RetrieveRecordsBasedOnPageSize
@PageSize int,
@PageIndex int
as
begin 
WITH LogEntries AS ( 
SELECT  p.* ,ROW_NUMBER() OVER (ORDER BY Id)
AS Row  
FROM Person p )

SELECT *
FROM LogEntries 
WHERE Row between (((@PageIndex - 1) * @PageSize) + 1) and @PageIndex * @PageSize
end

execute pro_RetrieveRecordsBasedOnPageSize 5, 1

step2: //---------- in aspx file-----------
here first,previous,next and last linkbuttons are placed in a table to navigate through the grid. here we are not using the event and propert of grid. AllowPaging property to false and donot use PageIndexChanging event.

<table border = "0" width = "700">
        <tr>
            <td align = "right"><asp:LinkButton ID="lnkbFirst" runat="server" Text = "First" ForeColor = "#0099FF" CommandName = "First" OnCommand = "ChangePage" ></asp:LinkButton></td>
            <td></td>
            <td align = "left"><asp:LinkButton ID="lnkbPrevious" runat="server" Text = "Prevoius" CommandName = "Previous" OnCommand="ChangePage" ForeColor = "#0099FF"></asp:LinkButton></td>         
            <td align = "right"></td>
            <td></td>                    
            <td align = "right"><asp:LinkButton ID="lnkbNext" runat="server" Text = "Next" CommandName = "Next" OnCommand="ChangePage" ForeColor = "#0099FF"></asp:LinkButton></td>
             <td></td>
             <td align = "left"><asp:LinkButton ID="lnkbLast" runat="server" Text = "Last" ForeColor = "#0099FF" OnCommand="ChangePage" CommandName = "Last"></asp:LinkButton></td>
        </tr>
    </table>

step3://----------- in the code behind file (c#)---------

//declare this in globaly
Connection connectionDb = new Connection(); // generate an object of class, connection 
DataSet dsRetrieve = new DataSet();
DataSet dsPaging = new DataSet();
int currentPageNumber;
private const int pageSize =5;

// set the paging button enable and disable
    public void ApplayPaging()   
   {
       // to matain the current page number between the post back
       currentPageNumber = (int)ViewState["currentPageNumber"];
       int totalPages;
       int maxRows = 0;
        dsRetrieve = connectionDb.Retrieve();   // retrieve the records 
        maxRows = dsRetrieve.Tables[0].Rows.Count;
        if (maxRows <= pageSize)
        {
            lnkbPrevious.Enabled = false;
            lnkbFirst.Enabled = false;
            lnkbNext.Enabled = false;
            lnkbLast.Enabled = false;
        }
        totalPages = CalculateTotalPages(maxRows);  // to find the total pages in the grid view
        if (currentPageNumber == 1)
        {
            lnkbPrevious.Enabled = false;
            lnkbFirst.Enabled = false;
            if (totalPages > 1)
            {
                lnkbNext.Enabled = true;
                lnkbLast.Enabled = true;
            }
            else
            {
                lnkbNext.Enabled = false;
                lnkbLast.Enabled = false;
            }
        }
        else
        {
            lnkbPrevious.Enabled = true;
            lnkbFirst.Enabled = true;
            if (currentPageNumber >= totalPages)
            {
                lnkbNext.Enabled = false;
                lnkbLast.Enabled = false;
            }
            else
            {
                lnkbNext.Enabled = true;
                lnkbLast.Enabled = true;
            }
        }            
   }

// to calculate the number of pages in a grid view
public int CalculateTotalPages(int maxRows)  
    {
        float maxRecords = (float)maxRows;
        float Pages = maxRecords / pageSize;
        int totalPage = (int)Pages;
        float point = Pages - (int)Pages;
        if (point < 1 && point > 0)
        {
            totalPage = totalPage + 1;
        }
        return totalPage;
    }

    // call this function using link button onCommand event..
    // navigation button in paging
    protected void ChangePage(object sender, CommandEventArgs e)   
    {
        currentPageNumber = (int)ViewState["currentPageNumber"];
        int totalPages;
        int maxRows = 0;
        dsRetrieve = connectionDb.Retrieve();  // retrieve the records

        // to find the total number of records in the table
        maxRows = dsRetrieve.Tables[0].Rows.Count;  // 

        // find the total pages in the grid view
        totalPages = CalculateTotalPages(maxRows);   
        switch (e.CommandName)
        {
            case "Previous":
                currentPageNumber = currentPageNumber - 1;             
                break;
            case "Next":
                currentPageNumber = currentPageNumber + 1;              
                break;
            case  "First":
                currentPageNumber = 1;               
                break;
            case "Last":
                currentPageNumber = totalPages;              
                break;
        }
        ViewState["currentPageNumber"] = currentPageNumber;
        fillGrid();  // bind data values to the grid view
    }

private void fillgrid()
{
         ApplayPaging(); 
        currentPageNumber = (int)ViewState["currentPageNumber"];
        dsPaging = connectionDb.Paging(pageSize, currentPageNumber); // call the paging function 
       // bind the dataset to the gridview
        grdManupulate.DataSource = dsPaging;   
        grdManupulate.DataBind();       
}

//page load
   protected void Page_Load(object sender, EventArgs e) 
   {       // execute for the first page load
       if (!IsPostBack)
        {                   
            currentPageNumber = 1;
            ViewState["currentPageNumber"] = currentPageNumber;                  
           Fillgrid(); // bind data values to the grid view
        }            
    }