class TestTimer
{
    public static void Main()
    {
        Timer timer = new Timer();
        timer.Elapsed += new ElapsedEventHandler( DisplayTimeEvent );
        timer.Interval = 1000;
        timer.Start();
        timer.Enabled = true;

        while ( Console.Read() != 'q' )
        {
             //-------------
        }
    }
    public static void DisplayTimeEvent( object source, ElapsedEventArgs e )
    {
        Console.Write(\r{0}, DateTime.Now);
    }
}
七、调用外部程序：
class Test
{
    static void Main(string[] args)
    {
        System.Diagnostics.Process.Start(notepad.exe);
    }
}

ADO.NET方面的：
八、连接Access数据库：
using System;
using System.Data;
using System.Data.OleDb;

class TestADO
{
    static void Main(string[] args)
    {
        string strDSN = Provider=Microsoft.Jet.OLEDB.4.0;Data Source=c:\\test.mdb;
        string strSQL = SELECT * FROM employees ;

        OleDbConnection conn = new OleDbConnection(strDSN);
        OleDbCommand cmd = new OleDbCommand( strSQL, conn );
        OleDbDataReader reader = null;
        try
        {
            conn.Open();
            reader = cmd.ExecuteReader();
            while (reader.Read() )
            {
                Console.WriteLine(First Name:{0}, Last Name:{1}, reader[FirstName], reader[LastName]);
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }
        finally
        {
            conn.Close();
        }
    }
}
九、连接SQL Server数据库：
using System;
using System.Data.SqlClient;