Using ADO.NET programmatically with C#

2005/10/23	14:17	Library Manager Visual C#.NET, ADO.NET, SQL
					Just started to develop the app.
					Created mainForm, replaced a menu, a toolbar, and
					a statusbar control.
2005/10/27	23:36	created database : Library, and Books table.
					created images n added to imagelist
					added buttons, arranged statusbar				
					arranged menu.
2005/10/28	23:11	Added textboxes, labels, and a datagrid.
					Added about form.
2005/11/05	08:41	Redesigned the database.(added Code)
					Added DataManipulationClass to FormMain.
					Done some arrangements with the controls.
					Done synchronization of the textboxes and the datagrid.
			23:10	Added AddData function, done some modifications on controls	
2005/11/06	10:01	Added Delete, Search and Reload features.
					Need some improvements about deletion and addition (see D001,D002)
2005/11/07	23:15	Added Modify feature, and arranged menu items, arranged aboutform.(see D003)
2005/11/09	23:47	Tested a bug was found (E001)
					Some arrangements on code.
2005/11/12	14:39	Replaced parameters to sql queries in ModifyData, DeleteData, 
					SearchData, and AddData functions.
					Added more remarks to code.
			15:05	fixed E001 if the textbox is null then assign the value to 0.			
2005/12/13	01:07	Added a new feature to create the database, the table used by this program
					and inserted an initial row.
					Added a menu group and an item Create Database to use the feature above.
			22:58	Added BookID Coloumn to dataGrid and Done Modify and Delete Queries according
					to it. fixed D001 and D002

Debug 

-D001 DeleteData() must delete only selected data row.
D002 AddData() must check whether the necessary columnns textboxes filled.
-D003 ModifyData must also modify Title column


Error

-E001 System.FormatException when modifying a null textbox


			int iposition;
			mycm=(CurrencyManager)this.BindingContext[datac.myds,"users"];
			iposition=mycm.Position+1;
			label1.Text=iposition.ToString();