databounddataset.cs

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using System;
using System.Web;
using System.Web.UI;
using System.Collections;
using System.Data;

namespace myControls {
	[ParseChildren(true)]
	public class DataBoundDataSet : Control {

		private object _dataSource;
		private string _dataMember = String.Empty;
		private ITemplate _itemTemplate; 

		public object DataSource {
			get {
				return _dataSource;
			}
			set {
				_dataSource = value;
			}
		}
	
		public string DataMember {
			get {
				return _dataMember;
			}
			set {
				_dataMember = value;
			}
		}

		private IEnumerable GetDataSource(object DataSource, string Datamember) {
			if (DataSource is IEnumerable) {
				return (IEnumerable)DataSource;
			} else if (DataSource is DataSet) {
				if (DataMember != String.Empty) {
					return ((DataSet)DataSource).Tables[DataMember].DefaultView;
				} else {
					return ((DataSet)DataSource).Tables[0].DefaultView;
				}
			} else {
				throw new ArgumentException( "Invalid data source!" );
			}
		}

		protected override void OnDataBinding(EventArgs e) {
			IEnumerator objDataEnum;
			DataBoundDataSetItem objItem;
			int intCounter=0;

			if (DataSource != null) {
				Controls.Clear();
				ClearChildViewState();

				objDataEnum = GetDataSource( _dataSource, _dataMember ).GetEnumerator();

				while ( objDataEnum.MoveNext() ) {
					objItem = new DataBoundDataSetItem( objDataEnum.Current );
					ItemTemplate.InstantiateIn( objItem );
					Controls.Add( objItem );
					intCounter++;
				}
				ViewState["NumItems"] = intCounter;
				ChildControlsCreated = true;
			}
		}

		protected override void CreateChildControls() {
			object objNumItems;
			int intItemCount;
			int intCounter;
			DataBoundDataSetItem objItem;

			objNumItems = ViewState["NumItems"];
			if (objNumItems != null) {
				Controls.Clear();
				intItemCount = (int)objNumItems;
				for (intCounter = 0; intCounter<intItemCount;intCounter++) {
					objItem  = new DataBoundDataSetItem( null );
					ItemTemplate.InstantiateIn( objItem );
					Controls.Add( objItem );
				}
			}
		}

		[TemplateContainer(typeof(DataBoundDataSetItem))]
		public ITemplate ItemTemplate {
			get {
				return _itemTemplate;
			}
			set {
				_itemTemplate = value;
			}
		}
	}

	public class DataBoundDataSetItem :	Control, INamingContainer {

		private object _DataItem;

		public DataBoundDataSetItem( object DataItem ) : base() {
			_DataItem = DataItem;
		}

		public object DataItem {
			get {
				return _DataItem;
			}
		}
	}
}