GUI Windows Forms C# Tutorial

using System;
using System.Drawing;
using System.Windows.Forms;
public class NotifyIconTimerUpdate : Form
{
    private Icon[] images = new Icon[8];
    int index = 0;
    public NotifyIconTimerUpdate()
    {
        InitializeComponent();
        images[0] = new Icon("1.ico");
        images[1] = new Icon("2.ico");
        images[2] = new Icon("3.ico");
        images[3] = new Icon("4.ico");
        images[4] = new Icon("5.ico");
        images[5] = new Icon("1.ico");
        images[6] = new Icon("2.ico");
        images[7] = new Icon("3.ico");
    }
    private void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
    {
        notifyIcon.Icon = images[index];
        index++;
        if (index > 7) 
           index = 0;
    }
    [STAThread]
    public static void Main(string[] args)
    {
        Application.Run(new NotifyIconTimerUpdate());
    }
    private System.Windows.Forms.NotifyIcon notifyIcon;
    private System.Timers.Timer timer;
    
    private System.ComponentModel.IContainer components = null;
    private void InitializeComponent()
    {
        this.components = new System.ComponentModel.Container();
        this.notifyIcon = new System.Windows.Forms.NotifyIcon(this.components);
        this.timer = new System.Timers.Timer();
        ((System.ComponentModel.ISupportInitialize)(this.timer)).BeginInit();
        this.SuspendLayout();
        // 
        // notifyIcon
        // 
        this.notifyIcon.Text = "notifyIcon1";
        this.notifyIcon.Visible = true;
        // 
        // timer
        // 
        this.timer.Enabled = true;
        this.timer.Interval = 1000;
        this.timer.SynchronizingObject = this;
        this.timer.Elapsed += new System.Timers.ElapsedEventHandler(this.timer_Elapsed);
        // 
        // NotifyIconTimerUpdate
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
        this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
        this.ClientSize = new System.Drawing.Size(340, 174);
        ((System.ComponentModel.ISupportInitialize)(this.timer)).EndInit();
        this.ResumeLayout(false);
    }
}