using System;
using System.Threading;
using System.Windows.Forms;
static class Program
{
public static EventWaitHandle ProgramStarted;
[STAThread]
static void Main()
{
// 尝试创建一个命名事件
bool createNew;
ProgramStarted = new EventWaitHandle(false, EventResetMode.AutoReset, "MyStartEvent", out createNew);
// 如果该命名事件已经存在(存在有前一个运行实例),则发事件通知并退出
if (!createNew)
{
ProgramStarted.Set();
return;
}
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
}
C# code
// Form1.cs
//
using System;
using System.Windows.Forms;
using System.Threading;
public partial class Form1 : Form
{
NotifyIcon notifyIcon1 = new NotifyIcon();
public Form1()
{
//InitializeComponent();
this.notifyIcon1.Text = "Double click me to show window";
this.notifyIcon1.Icon = System.Drawing.SystemIcons.Information;
this.notifyIcon1.DoubleClick += OnNotifyIconDoubleClicked;
this.SizeChanged += OnSizeChanged;
ThreadPool.RegisterWaitForSingleObject(Program.ProgramStarted, OnProgramStarted, null, -1, false);
}
// 当最小化时,放到系统托盘。
void OnSizeChanged(object sender, EventArgs e)
{
if (this.WindowState == FormWindowState.Minimized)
{
this.notifyIcon1.Visible = true;
this.Visible = false;
}
}
// 当双击托盘图标时,恢复窗口显示
void OnNotifyIconDoubleClicked(object sender, EventArgs e)
{
this.Visible = true;
this.notifyIcon1.Visible = false;
this.WindowState = FormWindowState.Normal;
}
// 当收到第二个进程的通知时,显示气球消息
void OnProgramStarted(object state, bool timeout)
{
this.notifyIcon1.ShowBalloonTip(2000, "Hello", "I am here...", ToolTipIcon.Info);
}
}