ASP.NET Expand/Contract DataGrid

// ---------------------------------------------------------
// Tony Truong's ExDataGrid
// Copyright (C) 2004 
// For further reference see http://www.codeproject.com
// ---------------------------------------------------------
// Much of the code below was written using elements from 
// Denis Baurer's HierarGrid server control
// ---------------------------------------------------------

using System;
using System.Collections;
using System.Data;
using System.IO;
using System.Resources;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace Gorth.ExDataGrids
{
	/// <summary>
	/// The ExColumn is derived from the BoundColumn and simply add's id's to each row entry of the column
	/// </summary>
	public class ExColumn : System.Web.UI.WebControls.BoundColumn 
	{
		#region Property: ExGroupName
		private string _exGroupName;

		/// <summary>
		/// Specifies the column name that is the basis for template filename <see cref="TemplateCachingBase">caching</see>
		/// </summary>
		public string ExGroupName
		{
			get { return _exGroupName; }
			set { _exGroupName = value; }
		}
		#endregion Property: ExGroupName

		#region Property: DrawBorders
		private bool _drawBorders;

		/// <summary>
		/// Specifies the column name that is the basis for template filename <see cref="TemplateCachingBase">caching</see>
		/// </summary>
		public bool DrawBorders
		{
			get { return _drawBorders; }
			set { _drawBorders = value; }
		}
		#endregion Property: DrawBorders

		#region Property: BackColor
		private string _backColor;

		/// <summary>
		/// Specifies the column name that is the basis for template filename <see cref="TemplateCachingBase">caching</see>
		/// </summary>
		public string BackColor
		{
			get { return _backColor; }
			set { _backColor = value; }
		}
		#endregion Property: BackColor

		#region Property: ForeColor
		private string _foreColor;

		/// <summary>
		/// Specifies the column name that is the basis for template filename <see cref="TemplateCachingBase">caching</see>
		/// </summary>
		public string ForeColor
		{
			get { return _foreColor; }
			set { _foreColor = value; }
		}
		#endregion Property: ForeColor

		#region Property: Width
		private int _width;

		/// <summary>
		/// Specifies the column name that is the basis for template filename <see cref="TemplateCachingBase">caching</see>
		/// </summary>
		public int Width
		{
			get { return _width; }
			set { _width = value; }
		}
		#endregion Property: Width

		/// <summary>
		/// Initializes a new instance of HierarColumn class.
		/// </summary>
		public ExColumn() : base()
		{
			_drawBorders = false;
			_backColor = "none";
			_foreColor = "none";
			_width = -1;
		}

		/// <summary>
		/// On initialization the ExColumn hide the columns and set the id/class names
		/// 
		/// </summary>
		/// <param name="cell"></param>
		/// <param name="columnIndex"></param>
		/// <param name="itemType"></param>
		public override void InitializeCell(TableCell cell, int columnIndex, ListItemType itemType)
		{
			base.InitializeCell(cell, columnIndex, itemType);
			switch(itemType)
			{
				case ListItemType.Item:
				case ListItemType.AlternatingItem:
				case ListItemType.SelectedItem:
					cell.CssClass=_exGroupName;
					if(_drawBorders)
					{
						cell.Attributes.Add("style", "display:none");
					}
					else
					{
						cell.Attributes.Add("style", "display:none;border-style=none");
					}

					//add backcolor
					if(BackColor != "none")
					{
						cell.Attributes.Add("style", cell.Attributes["style"] + ";background-color:" + BackColor);
					}

					//add forecolor
					if(ForeColor != "none")
					{
						cell.Attributes.Add("style", cell.Attributes["style"] + ";color:" + ForeColor);
					}

					break;
				case ListItemType.Header:
					cell.CssClass=_exGroupName;
					if(_drawBorders)
					{
						cell.Attributes.Add("style", "display:none");
					}
					else
					{
						cell.Attributes.Add("style", "display:none;border-bottom-style=solid;border-left-style=none;border-right-style=none;border-top-style=none");
					}

					//add backcolor
					if(BackColor != "none")
					{
						cell.Attributes.Add("style", cell.Attributes["style"] + ";background-color:" + BackColor);
					}

					//add width
					if(Width != -1)
					{
						cell.Attributes.Add("style", cell.Attributes["style"] + ";width:" + Width.ToString() + "px");
					}

					break;
				case ListItemType.Footer:
					cell.CssClass=_exGroupName;
					if(_drawBorders)
					{
						cell.Attributes.Add("style", "display:none");
					}
					else
					{
						cell.Attributes.Add("style", "display:none;border-bottom-style=solid;border-left-style=none;border-right-style=none;border-top-style=solid");
					}

					//add backcolor
					if(BackColor != "none")
					{
						cell.Attributes.Add("style", cell.Attributes["style"] + ";background-color:" + BackColor);
					}

					break;
				case ListItemType.EditItem:
					break;
			}
		}
	}

	/// <summary>
	/// The ExColumnExpand is derived from the BoundColumn and contains an image with a plus/minus icon 
	/// on the header of the column. It is used to expand the ExColumn column class
	/// </summary>
	public class ExColumnExpand : System.Web.UI.WebControls.BoundColumn 
	{
		#region Property: ExGroupName
		private string _exGroupName;

		/// <summary>
		/// Specifies the column name that is the basis for template filename <see cref="TemplateCachingBase">caching</see>
		/// </summary>
		public string ExGroupName
		{
			get { return _exGroupName; }
			set { _exGroupName = value; }
		}
		#endregion Property: ExGroupName

		/// <summary>
		/// Initializes a new instance of ExColumnExpand class.
		/// </summary>
		public ExColumnExpand() : base()
		{
		}

		/// <summary>
		/// On initialization the ExColumnExpand adds a plus image to right of the header
		/// </summary>
		/// <param name="cell"></param>
		/// <param name="columnIndex"></param>
		/// <param name="itemType"></param>
		public override void InitializeCell(TableCell cell, int columnIndex, ListItemType itemType)
		{
			string divCssClass = String.Empty;

			base.InitializeCell(cell, columnIndex, itemType);

			switch(itemType)
			{
				case ListItemType.Header:
					Image image = new Image();
					image.ID = "Icon";
					image.ImageUrl = "~/images/plus.gif";
					image.Attributes.Add("onClick", "javascript:ToggleExpand('" + _exGroupName + "', this, '" + this.Owner.ID + "');");
					image.ID = this._exGroupName.ToString() + "_ctl_Icon";
					Label headerText = new Label();
					headerText.Text = cell.Text;

					cell.Controls.Add(headerText);
					cell.Controls.Add(image);

					break;
			}
		}
	}
}