Paging, Selecting, Deleting, Editing and Sorting in the ASP.NET GridView Control with Keyboard Shortcuts

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Text;
using System.Threading;
using System.Collections.Generic;

public partial class AjaxGridControl : System.Web.UI.UserControl
{

    #region private fields
    private int gridId=0;
    AjaxGrid.GridProfileData profile;
    #endregion private fields


    #region public properties
    public int GridId { get { return gridId; } set { gridId = value; } }
    #endregion

    protected void Page_Load(object sender, EventArgs e)
    {
        bool outputPage = true;
        List<AjaxGrid.GridProfileData> profiles = (List<AjaxGrid.GridProfileData>)Session["GridProfile"];
        profile = profiles [gridId];

        if (IsPostBack)
        {   // intercept postbacks and action them before repainting
            // (they may well jump to another page and make repaint of current table redundant)
            if (profile.SelectProc != null && Request.Form["__EVENTTARGET"] == "AJAXGRID" + gridId.ToString())
            {
                profile.SelectProc(AjaxGrid.SafeInt(Request.Form["__EVENTARGUMENT"]));
            }
            else if (Request.Form["__EVENTTARGET"] == "AJAXCSV") // postback was used to output CSV file
            {                                                    // initiate asynchronous call to output csv
                outputPage = false;
            }
        }

        // synchronous call to populate grid commented out below..
        // divGrid.InnerHtml = AjaxGrid.Paint(Session["GridProfile"], gridId);
        // initiate asynchronous call to populate grid or CSV
        AjaxGrid.StateObject stateObject = new AjaxGrid.StateObject(profile, gridId, outputPage);
        EndEventHandler endproc = (outputPage) ? new EndEventHandler(EndProc) : new EndEventHandler(EndProcCSV);
        PageAsyncTask task = new PageAsyncTask(
                    new BeginEventHandler(stateObject.BeginProc),
                    endproc,
                    new EndEventHandler(TimeoutProc),
                    stateObject
                );
        Page.RegisterAsyncTask(task);
    }

    #region aynchronous I/O completion
    // asynchronous database read failed...
    void TimeoutProc(IAsyncResult result) // default timeout is 45 sec
    {
        AjaxGrid.StateObject stateObject = (AjaxGrid.StateObject)result.AsyncState;
        stateObject.Dispose();
    }

    // asynchronous database read has completed, we can now populate grid with the results
    public void EndProc(IAsyncResult result)
    {
        AjaxGrid.StateObject stateObject = (AjaxGrid.StateObject)result.AsyncState;
        try
        {
            divGrid.InnerHtml = AjaxGrid.Paint(stateObject.EndProc(result), profile, gridId);
        }
        finally
        {
            stateObject.Dispose();
        }
    }

    // asynchronous database read has completed, we can now generate a CSV from the results
    public void EndProcCSV(IAsyncResult result)
    {
        AjaxGrid.StateObject stateObject = (AjaxGrid.StateObject)result.AsyncState;
        try
        {
            string csv = AjaxGrid.CreateCSV (stateObject.EndProc(result),gridId);
            AjaxGrid.OutputCsvFile(this.Response, csv, "export.csv");
        }
        finally
        {
            stateObject.Dispose();
        }
    }
    #endregion aynchronous I/O completion

}