当前上下文中不存在名称“notifyIcon1”

我刚接触c#,尝试编写代码时不使用与。
我正在尝试构建一个系统托盘应用程序,它将在运行时更改notifyIcon。

我阅读了一些关于该主题的教程,并编写了以下代码,但我遇到了这些错误,无法解决:

new 2.cs(41,9):error CS0103:当前上下文中不存在名称“notifyIcon1”
new 2.cs(41,37):error CS0026:关键字“this”在静态属性、静态方法或静态字段初始值设定项中无效

有人能帮我吗?(这是我的代码的精简版……试图隔离问题。)

using System;
using System.Windows.Forms;
using System.Threading;
using System.Drawing;
using System.Diagnostics;

namespace sysTrayApp
{
   static class Program
   {
    [STAThread]
    static void Main()
    {
         Application.EnableVisualStyles();
         Application.SetCompatibleTextRenderingDefault(false);
         NotifyIcon notifyIcon1 = new NotifyIcon();
         ContextMenu contextMenu1 = new ContextMenu();
         MenuItem menuItem1 = new MenuItem();
         contextMenu1.MenuItems.AddRange(new MenuItem[] { menuItem1 });

         menuItem1.Index = 0;
         menuItem1.Text = "Exit";
         menuItem1.Click += new EventHandler(menuItem1_Click);

         notifyIcon1.Icon = new Icon("On.ico");
         notifyIcon1.Text = "some text";
         notifyIcon1.ContextMenu = contextMenu1;
         notifyIcon1.Click += new EventHandler(notifyIcon1_Click);
         notifyIcon1.Visible = true; 

        Application.Run();
    }

    private static void menuItem1_Click(object Sender, System.EventArgs e)
    {
         Application.Exit();
    }

    private static void notifyIcon1_Click(object Sender, EventArgs e)
    {
        notifyIcon1.Icon = new Icon(this.GetType(),"Off.ico");
    }
  }
}