Database Helper Class Library to Ease Database Operation

///////////////////////////////////////////////////////////////////////////
// Copyright 2003-2005 Falcon Soon
//
// Author: Soon Chun Boon
// Date: 10 Jan 2004
// Description: 
// Base class for Database Interaction.
// Because this class implements IDisposable, derived classes shouldn't do so.
// This class is taken from codes generated by LLBLGen v1.21.2003.712
///////////////////////////////////////////////////////////////////////////

using System;
using System.Data;

namespace DBHelper
{
	/// <summary>
	/// Error Enums used by this library.
	/// </summary>
	public enum DBError
	{
        /// <summary>
        /// Everyting is Ok.
        /// </summary>
		AllOk
		// Add more here (check the comma's!)
	}


	/// <summary>
	/// General interface which contains only common database methods of all classes.
	/// </summary>
	public interface ICommonDBAccess
	{
        /// <summary>
        /// General signature for database insert operation.
        /// </summary>
        /// <returns>True if successful.</returns>
		bool		Insert();

        /// <summary>
        /// General signature for database update operation.
        /// </summary>
        /// <returns>True if successful.</returns>
		bool		Update();

        /// <summary>
        /// General signature for database delete operation.
        /// </summary>
        /// <returns>True if successful.</returns>
		bool		Delete();

        /// <summary>
        /// General signature for database select operation based on select criteria.
        /// </summary>
        /// <returns>A <see cref="System.Data.DataTable"/> consists of selected rows.</returns>
		DataTable	SelectSome();

        /// <summary>
        /// General signature for database select all operation.
        /// </summary>
        /// <returns>A <see cref="System.Data.DataTable"/> consists of all rows in database.</returns>
		DataTable	SelectAll();

        /// <summary>
        /// General signarute for database operation using <see cref="System.Data.Common.DataAdapter.Update"/>.
        /// </summary>
        /// <returns>The number of rows successfully updated.</returns>
        int         DBAdapterUpdate();

        /// <summary>
        /// Specifies fields to select from database.
        /// </summary>
        string FieldsToSelect
        {
            get;
            set;
        }

        /// <summary>
        /// Specifies fields to update to database.
        /// </summary>
        string FieldsToUpdate
        {
            get;
            set;
        }

        /// <summary>
        /// Specifies filter expression for select operation.
        /// </summary>
        string SelectCriteria
        {
            get;
            set;
        }

        /// <summary>
        /// Specifies filter expression for update operation.
        /// </summary>
        string UpdateCriteria
        {
            get;
            set;
        }

        /// <summary>
        /// Specifies filter expression for delete operation.
        /// </summary>
        string DeleteCriteria
        {
            get;
            set;
        }
	}


	/// <summary>
	/// Abstract base class for Database Interaction classes.
	/// </summary>
	public abstract class DBInteractionBase
	{
		#region Class Member Declarations
            /// <summary>
            /// Number of rows affected by database operation.
            /// </summary>
			protected	int						miRowsAffected;

            /// <summary>
            /// Error code.
            /// </summary>
			protected	int     				miErrorCode;

            /// <summary>
            /// Connection string.
            /// </summary>
			protected	string					mstrConnectionString;
		#endregion


		/// <summary>
		/// Protected class constructor.
		/// </summary>
		protected DBInteractionBase()
		{
			// Initialize the class' members.
			InitClass();
		}


		/// <summary>
		/// Initializes class members.
		/// </summary>
		protected virtual void InitClass()
		{
			// create all the objects and initialize other members.
            miRowsAffected = 0;
			miErrorCode = (int)DBError.AllOk;
            mstrConnectionString = "";
		}


		#region Class Property Declarations
        /// <summary>
        /// Return error code.
        /// </summary>
		public int ErrorCode
		{
			get
			{
				return (miErrorCode);
			}
		}

        /// <summary>
        /// Specifies connection string.
        /// </summary>
		public virtual string ConnectionString
		{
			get
			{
				return (mstrConnectionString);
			}
			set
			{
				mstrConnectionString = value;
			}
		}

        /// <summary>
        /// Returns rows affected by database operation.
        /// </summary>
		public int RowsAffected
		{
			get
			{
				return (miRowsAffected);
			}
		}
		#endregion
	}
}