source2.cs

// <Snippet2>
using System;
using System.IO;

class DirAppend
{
    public static void Main()
    {
        using (StreamWriter w = File.AppendText("log.txt"))
        {
            Log("Test1", w);
            Log("Test2", w);
        }
        
        using (StreamReader r = File.OpenText("log.txt"))
        {
            DumpLog(r);
        }
    }

    public static void Log(string logMessage, TextWriter w)
    {
        w.Write("\r\nLog Entry : ");
        w.WriteLine("{0} {1}", DateTime.Now.ToLongTimeString(),
            DateTime.Now.ToLongDateString());
        w.WriteLine("  :");
        w.WriteLine("  :{0}", logMessage);
        w.WriteLine ("-------------------------------");
    }

    public static void DumpLog(StreamReader r)
    {
        string line;
        while ((line = r.ReadLine()) != null)
        {
            Console.WriteLine(line);
        }
    }
}
// </Snippet2>