sqlhelper.cs

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		{
			//create & open a SqlConnection, and dispose of it after we are done.
			using (SqlConnection cn = new SqlConnection(connectionString))
			{
				cn.Open();

				//call the overload that takes a connection in place of the connection string
				return ExecuteDataTable(cn, commandType, commandText, commandParameters);
			}
		}



		/// <summary>
		/// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection. 
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  DataTable dt = ExecuteDataTable(conn, CommandType.StoredProcedure, "GetOrders");
		/// </remarks>
		/// <param name="connection">a valid SqlConnection</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <returns>a DataTable containing the resultset generated by the command</returns>
		public static DataTable ExecuteDataTable(SqlConnection connection, CommandType commandType, string commandText)
		{
			//pass through the call providing null for the set of SqlParameters
			return ExecuteDataTable(connection, commandType, commandText, (SqlParameter[])null);
		}
		
		/// <summary>
		/// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection 
		/// using the provided parameters.
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  DataTable dt = ExecuteDataTable(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
		/// </remarks>
		/// <param name="connection">a valid SqlConnection</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
		/// <returns>a DataTable containing the resultset generated by the command</returns>
		public static DataTable ExecuteDataTable(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
		{
			//create a command and prepare it for execution
			SqlCommand cmd = new SqlCommand();
			PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters);
			
			//create the DataAdapter & DataTable
			SqlDataAdapter da = new SqlDataAdapter(cmd);
			DataTable dt = new DataTable();

			//fill the DataTable using default values for DataTable names, etc.
			da.Fill(dt);
			
			// detach the SqlParameters from the command object, so they can be used again.			
			cmd.Parameters.Clear();
			
			//return the DataTable
			return dt;						
		}
		

		/// <summary>
		/// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction. 
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  DataTable dt = ExecuteDataTable(trans, CommandType.StoredProcedure, "GetOrders");
		/// </remarks>
		/// <param name="transaction">a valid SqlTransaction</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <returns>a DataTable containing the resultset generated by the command</returns>
		public static DataTable ExecuteDataTable(SqlTransaction transaction, CommandType commandType, string commandText)
		{
			//pass through the call providing null for the set of SqlParameters
			return ExecuteDataTable(transaction, commandType, commandText, (SqlParameter[])null);
		}
		
		/// <summary>
		/// Execute a SqlCommand (that returns a resultset) against the specified SqlTransaction
		/// using the provided parameters.
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  DataTable dt = ExecuteDataTable(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
		/// </remarks>
		/// <param name="transaction">a valid SqlTransaction</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
		/// <returns>a DataTable containing the resultset generated by the command</returns>
		public static DataTable ExecuteDataTable(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
		{
			//create a command and prepare it for execution
			SqlCommand cmd = new SqlCommand();
			PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters);
			
			//create the DataAdapter & DataTable
			SqlDataAdapter da = new SqlDataAdapter(cmd);
			DataTable dt = new DataTable();

			//fill the DataTable using default values for DataTable names, etc.
			da.Fill(dt);
			
			// detach the SqlParameters from the command object, so they can be used again.
			cmd.Parameters.Clear();
			
			//return the DataTable
			return dt;
		}
		


		#endregion ExecuteDataTable
		
		#region ExecuteReader

		/// <summary>
		/// this enum is used to indicate whether the connection was provided by the caller, or created by SqlHelper, so that
		/// we can set the appropriate CommandBehavior when calling ExecuteReader()
		/// </summary>
		private enum SqlConnectionOwnership	
		{
			/// <summary>Connection is owned and managed by SqlHelper</summary>
			Internal, 
			/// <summary>Connection is owned and managed by the caller</summary>
			External
		}

		/// <summary>
		/// Create and prepare a SqlCommand, and call ExecuteReader with the appropriate CommandBehavior.
		/// </summary>
		/// <remarks>
		/// If we created and opened the connection, we want the connection to be closed when the DataReader is closed.
		/// 
		/// If the caller provided the connection, we want to leave it to them to manage.
		/// </remarks>
		/// <param name="connection">a valid SqlConnection, on which to execute this command</param>
		/// <param name="transaction">a valid SqlTransaction, or 'null'</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <param name="commandParameters">an array of SqlParameters to be associated with the command or 'null' if no parameters are required</param>
		/// <param name="connectionOwnership">indicates whether the connection parameter was provided by the caller, or created by SqlHelper</param>
		/// <returns>SqlDataReader containing the results of the command</returns>
		private static SqlDataReader ExecuteReader(SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters, SqlConnectionOwnership connectionOwnership)
		{	
			//create a command and prepare it for execution
			SqlCommand cmd = new SqlCommand();
			PrepareCommand(cmd, connection, transaction, commandType, commandText, commandParameters);
			
			//create a reader
			SqlDataReader dr;

			// call ExecuteReader with the appropriate CommandBehavior
			if (connectionOwnership == SqlConnectionOwnership.External)
			{
				dr = cmd.ExecuteReader();
			}
			else
			{
				dr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
			}
			
			// detach the SqlParameters from the command object, so they can be used again.
			cmd.Parameters.Clear();
			
			return dr;
		}

		/// <summary>
		/// Execute a SqlCommand (that returns a resultset and takes no parameters) against the database specified in 
		/// the connection string. 
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders");
		/// </remarks>
		/// <param name="connectionString">a valid connection string for a SqlConnection</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <returns>a SqlDataReader containing the resultset generated by the command</returns>
		public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText)
		{
			//pass through the call providing null for the set of SqlParameters
			return ExecuteReader(connectionString, commandType, commandText, (SqlParameter[])null);
		}

		/// <summary>
		/// Execute a SqlCommand (that returns a resultset) against the database specified in the connection string 
		/// using the provided parameters.
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  SqlDataReader dr = ExecuteReader(connString, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
		/// </remarks>
		/// <param name="connectionString">a valid connection string for a SqlConnection</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
		/// <returns>a SqlDataReader containing the resultset generated by the command</returns>
		public static SqlDataReader ExecuteReader(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
		{
			//create & open a SqlConnection
			SqlConnection cn = new SqlConnection(connectionString);
			cn.Open();

			try
			{
				//call the private overload that takes an internally owned connection in place of the connection string
				return ExecuteReader(cn, null, commandType, commandText, commandParameters,SqlConnectionOwnership.Internal);
			}
			catch
			{
				//if we fail to return the SqlDatReader, we need to close the connection ourselves
				cn.Close();
				throw;
			}
		}

		/// <summary>
		/// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection. 
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  SqlDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders");
		/// </remarks>
		/// <param name="connection">a valid SqlConnection</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <returns>a SqlDataReader containing the resultset generated by the command</returns>
		public static SqlDataReader ExecuteReader(SqlConnection connection, CommandType commandType, string commandText)
		{
			//pass through the call providing null for the set of SqlParameters
			return ExecuteReader(connection, commandType, commandText, (SqlParameter[])null);
		}

		/// <summary>
		/// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection 
		/// using the provided parameters.
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  SqlDataReader dr = ExecuteReader(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
		/// </remarks>
		/// <param name="connection">a valid SqlConnection</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
		/// <param name="commandText">the stored procedure name or T-SQL command</param>
		/// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
		/// <returns>a SqlDataReader containing the resultset generated by the command</returns>
		public static SqlDataReader ExecuteReader(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
		{
			//pass through the call to the private overload using a null transaction value and an externally owned connection
			return ExecuteReader(connection, (SqlTransaction)null, commandType, commandText, commandParameters, SqlConnectionOwnership.External);
		}

	
		/// <summary>
		/// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction. 
		/// </summary>
		/// <remarks>
		/// e.g.:  
		///  SqlDataReader dr = ExecuteReader(trans, CommandType.StoredProcedure, "GetOrders");
		/// </remarks>
		/// <param name="transaction">a valid SqlTransaction</param>
		/// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>