AsyncCallback and file viewer : Asynchronous « Thread « C# / CSharp Tutorial

1. C# / CSharp Tutorial
2. Thread
3. Asynchronous

using System;
using System.IO;
using System.Text;

public class FileViewer
{
    FileStream license;
    private AsyncCallback doneDelegate;
    private byte[] buff = new byte[100];

    public FileViewer()
    {
        license = new FileStream("C:\\your.txt", FileMode.Open);
        doneDelegate = new AsyncCallback(UpdateConsole);

        if (buff[0] > 0)
        {
            license.BeginRead(buff, 0, buff.Length, doneDelegate, this);
        }
    }

    public void UpdateConsole(IAsyncResult result)
    {
        int totalBytes = license.EndRead(result);
        if (totalBytes > 0)
        {
            String s = Encoding.ASCII.GetString(buff, 0, totalBytes);
            Console.WriteLine(s);
        }
        if (buff[0] > 0)
        {
            license.BeginRead(buff, 0, buff.Length, doneDelegate, this);
        }
    }
}