Group GridView Data

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web.UI.WebControls;
using System.Web.UI;
using System.ComponentModel;
using System.Collections;
using System.Data;

// Written by Anurag Gandhi.
// Url: http://www.gandhisoft.com
// Contact me at: soft.gandhi@gmail.com

namespace GroupGridViewCtrl
{
    public class GroupGridView : GridView
    {
        private ITemplate _GroupHeaderTemplate;
        private ITemplate _GroupFooterTemplate;
        private int _totalColumns;

        private DefaultState _DefaultState = DefaultState.Expanded;

        public DefaultState DefaultState
        {
            get { return _DefaultState; }
            set { _DefaultState = value; }
        }

        private Animation _AnimationSpeed = Animation.Fast;

        public Animation AnimationSpeed
        {
            get { return _AnimationSpeed; }
            set { _AnimationSpeed = value; }
        }

        private bool _AllowGrouping = false;

        public bool AllowGrouping
        {
            get { return _AllowGrouping; }
            set { _AllowGrouping = value; }
        }
        private string _GroupColumnName = string.Empty;

        public string GroupColumnName
        {
            get { return _GroupColumnName; }
            set { _GroupColumnName = value; }
        }

        [Browsable(false)]
        [PersistenceMode(PersistenceMode.InnerProperty)]
        [TemplateContainer(typeof(GroupContainer))]
        public ITemplate GroupHeaderTemplate
        {
            get { return _GroupHeaderTemplate; }
            set { _GroupHeaderTemplate = value; }
        }

        [Browsable(false)]
        [PersistenceMode(PersistenceMode.InnerProperty)]
        [TemplateContainer(typeof(GroupContainer))]
        public ITemplate GroupFooterTemplate
        {
            get { return _GroupFooterTemplate; }
            set { _GroupFooterTemplate = value; }
        }

        /// <summary>
        /// OverRiding PrepareControlHierarchy to instanciate the GroupHeader and GroupFooter Rows also in our GridView.//
        /// </summary>
        protected override void PrepareControlHierarchy()
        {
            base.PrepareControlHierarchy();

            Table t = (Table)Controls[0];
            if ((_GroupHeaderTemplate != null || _GroupFooterTemplate != null) && !String.IsNullOrEmpty(_GroupColumnName) && _AllowGrouping == true)
            {
                TableRow row = new TableRow();
                row.Style.Add("display", "none");
                t.Rows.AddAt(0, row);
                TableCell cell = new TableCell();
                cell.ColumnSpan = _totalColumns;
                row.Cells.Add(cell);

                DataTable _SourceTable = (DataTable)this.DataSource;
                var GroupList = (from x in _SourceTable.AsEnumerable() select new { Data = x.Field<object>(_GroupColumnName) }).Distinct();
                foreach (var Group in GroupList)
                {
                    if (_GroupHeaderTemplate != null)
                    {
                        GroupContainer HeaderContainer = new GroupContainer(this, _GroupColumnName, Group.Data);
                        _GroupHeaderTemplate.InstantiateIn(HeaderContainer);
                        Panel pHeader = new Panel();
                        pHeader.Attributes.Add("id", this.ClientID + "_GroupHeader_" + GetGroupData(Group.Data));
                        pHeader.Controls.Add(HeaderContainer);
                        cell.Controls.Add(pHeader);
                    }
                    if (_GroupFooterTemplate != null)
                    {
                        GroupContainer FooterContainer = new GroupContainer(this, _GroupColumnName, Group.Data);
                        _GroupFooterTemplate.InstantiateIn(FooterContainer);
                        Panel pFooter = new Panel();
                        pFooter.Attributes.Add("id", this.ClientID + "_GroupFooter_" + GetGroupData(Group.Data));
                        pFooter.Controls.Add(FooterContainer);
                        cell.Controls.Add(pFooter);
                    }
                }
                cell.DataBind();
            }
            return;
        }

        /// <summary>
        /// OverRiding OnRowCreated method.//
        /// </summary>
        /// <param name="e"></param>
        protected override void OnRowCreated(GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.DataRow)
            {
                //Adding "group" attribute to each row of the resulting table.//
                string GroupValue = GetGroupData(DataBinder.Eval(e.Row.DataItem, _GroupColumnName));
                e.Row.Attributes.Add("group", GroupValue);
            }
            base.OnRowCreated(e);
        }

        protected override void OnPreRender(EventArgs e)
        {
            base.OnPreRender(e);
            RenderClientSideGroup();
        }
        
        /// <summary>
        /// Overriding CreateColumns to get the total number of columns in GridView.//
        /// </summary>
        /// <param name="dataSource"></param>
        /// <param name="useDataSource"></param>
        /// <returns></returns>
        protected override ICollection CreateColumns(PagedDataSource dataSource, bool useDataSource)
        {
            ICollection coll = base.CreateColumns(dataSource, useDataSource);
            _totalColumns = coll.Count;
            return coll;
        }

        /// <summary>
        /// This is to remove any special character which may cause problem for javascript to run.//
        /// </summary>
        /// <param name="obj">Data based on which grouping needs to be done.</param>
        /// <returns>Data based on which grouping needs to be done (without special chars)</returns>
        private string GetGroupData(object obj)
        {
            string strData = Convert.ToString(obj);
            strData = strData.Replace(" ", "_");
            strData = strData.Replace("&", "_");
            return strData;
        }

        /// <summary>
        /// Renders the javascript/jquery to perform client side operation for grouping.//
        /// </summary>
        /// <returns>returns true if succeed</returns>
        public bool RenderClientSideGroup()
        {
            int ColCount = _totalColumns;
            string GridViewId = this.ClientID;
            string FadeOutScript, FadeInScript;

            switch (_AnimationSpeed)
            {
                case Animation.None:
                    FadeInScript = ".css('display', '')";
                    FadeOutScript = ".css('display', 'none')";
                    break;
                case Animation.Fast:
                    FadeInScript = ".fadeIn('fast')";
                    FadeOutScript = ".fadeOut('fast')";
                    break;
                case Animation.Slow:
                    FadeInScript = ".fadeIn('slow')";
                    FadeOutScript = ".fadeOut('slow')";
                    break;
                default:
                    FadeInScript = ".fadeIn()";
                    FadeOutScript = ".fadeOut()";
                    break;
            }

            StringBuilder sb = new StringBuilder();
            sb.AppendLine(" $(document).ready(function () {");
            sb.AppendLine("ApplyGrouping_" + this.ClientID + "();");
            if (this.DefaultState == GroupGridViewCtrl.DefaultState.Collapsed)
            {
                sb.AppendLine(string.Format(" $('#{0} tr[group]'){1};", GridViewId, FadeOutScript));
                sb.AppendLine(" $('#" + GridViewId + " tr[id^=GroupHeader]').attr('expanded', 'false');");
            }
            sb.AppendLine(" });");

            sb.AppendLine(" function ApplyGrouping_" + this.ClientID + "() {");
            sb.AppendLine(" var PrevText = '###', CurrText = '';");
            //sb.AppendLine(" $('#" + GridViewId + " tr:gt(1)').each(function (index) {");
            sb.AppendLine(" $('#" + GridViewId + " tr[group]').each(function (index) {");
            sb.AppendLine(" CurrText = $(this).attr('group');");
            sb.AppendLine(" if (PrevText != CurrText) {");
            //For Displaying Group Header and Footer.//
            if (_GroupFooterTemplate != null)
            {
                sb.AppendLine(" if (PrevText != '###' && $('#" + this.ClientID + "_GroupFooter_' + PrevText).length != 0)");
                sb.AppendLine(string.Format(" $(this).before('<tr id=\"GroupFooter' + PrevText + '\" expanded=\"true\"><td colspan=\"{0}\">' + $('#" + this.ClientID + "_GroupFooter_' + PrevText).html() + '</td></tr>');", ColCount));
            }
            sb.AppendLine(string.Format(" $(this).before('<tr id=\"GroupHeader' + CurrText + '\" expanded=\"true\" onclick=\"javascript:return Clicked_{1}(\\'' + CurrText + '\\');\" style=\"cursor:pointer;\"><td colspan=\"{0}\">' + $('#" + this.ClientID + "_GroupHeader_' + CurrText).html() + '</td></tr>');", ColCount, this.ClientID));
            sb.AppendLine("}");

            if (_GroupFooterTemplate != null)
            {
                sb.AppendLine(" if (index == " + (this.Rows.Count - 1).ToString() + " && $('#" + this.ClientID + "_GroupFooter_' + CurrText).length != 0)");
                sb.AppendLine(string.Format(" $(this).after('<tr id=\"GroupFooter' + CurrText + '\" expanded=\"true\"><td colspan=\"{0}\">' + $('#" + this.ClientID + "_GroupFooter_' + CurrText).html() + '</td></tr>');", ColCount));
            }
            sb.AppendLine(" PrevText = CurrText;");
            sb.AppendLine(" });");
            sb.AppendLine("}");

            sb.AppendLine(" ");
            sb.AppendFormat(" function Clicked_{0}(GroupId) {{", this.ClientID);
            sb.AppendLine(" if ($('#" + GridViewId + " tr#GroupHeader' + GroupId).attr('expanded') == 'true') {");
            sb.AppendLine(string.Format(" $('#{0} tr[group=' + GroupId + ']'){1};", GridViewId, FadeOutScript));
            sb.AppendLine(" $('#" + GridViewId + " tr#GroupHeader' + GroupId).attr('expanded', 'false');");
            sb.AppendLine(" }");
            sb.AppendLine(" else {");
            sb.AppendLine(string.Format(" $('#{0} tr[group=' + GroupId + ']'){1};", GridViewId, FadeInScript));
            sb.AppendLine(" $('#" + GridViewId + " tr#GroupHeader' + GroupId).attr('expanded', 'true');");
            sb.AppendLine(" }");
            sb.AppendLine(" }");

            this.Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "GroupScript" + this.ClientID, sb.ToString(), true);
            return true;
        }
    }

    /// <summary>
    /// Animation to decide the speed of FadeIn and FadeOut action.//
    /// </summary>
    public enum Animation
    {
        None = 0,
        Fast = 1,
        Slow = 2
    }

    public enum DefaultState
    {
        Collapsed = 0,
        Expanded = 1
    }
}