Question

我有一个问题吗？我用这种方式只运行一个程序实例。它做得非常好。但是当我在其他应用程序中使用这种方式时。当我通过桌面快捷方式运行其中一个程序时，两个程序都会在桌面上调用和显示。注意：两个程序都在windows系统中运行试试。

    static bool ok;
    static Mutex mutex = new Mutex(true, "{123Newsoft-Cleaner Portable Program123}",out ok);

    /// <summary>
    /// The main entry point for the application.
    /// </summary>
    [STAThread]

    static void Main()
    {
        //Application.EnableVisualStyles();
        //Application.SetCompatibleTextRenderingDefault(false);
        //Application.Run(new Form1());

        if (mutex.WaitOne(TimeSpan.Zero, true))  
        {

            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);


            var mainForm = new Form1c();

            try
            {                                    

                    mainForm.Visible = false;


                    mainForm.WindowState = FormWindowState.Normal;                  

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "error", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }

            Application.Run(mainForm);               

        }
        else
        {

            NativeMethods.PostMessage((IntPtr)NativeMethods.HWND_BROADCAST, NativeMethods.WM_SHOWME, IntPtr.Zero, IntPtr.Zero);

        }

// ----------------主要表格

    protected override void WndProc(ref Message M_C)
    {

        if (M_C.Msg == NativeMethods.WM_SHOWME)
        {               
            ShowMe();
        }
        base.WndProc(ref M_C);
    }

    //*************
    private void ShowMe()
    {

        if (WindowState == FormWindowState.Minimized)
        {
            Show();
            WindowState = FormWindowState.Normal;
        }

        // get our current "TopMost" value (ours will always be false though)
        bool top = TopMost;
        // make our form jump to the top of everything
        TopMost = true;
        // set it back to whatever it was
        TopMost = top;

    }

Answer 1

.NET Framework已经很好地支持了这一点。您想使用WindowsFormsApplicationBase类。将IsSingleInstance属性设置为true。您可以覆盖OnStartupNextInstance方法，以便在另一个实例启动时执行您喜欢的任何操作。就像恢复第一个实例的窗口一样。重写Program.cs文件，如下所示：

using System;
using System.Windows.Forms;
using Microsoft.VisualBasic.ApplicationServices;   // Add reference to Microsoft.VisualBasic

namespace WindowsFormsApplication1 {
    class Program : WindowsFormsApplicationBase {
        [STAThread]
        static void Main(string[] args) {
            var app = new Program();
            app.Run(args);
        }
        public Program() {
            this.IsSingleInstance = true;
            this.EnableVisualStyles = true;
            this.MainForm = new Form1();
        }
        protected override void OnStartupNextInstance(StartupNextInstanceEventArgs eventArgs) {
            if (this.MainForm.WindowState == FormWindowState.Minimized) this.MainForm.WindowState = FormWindowState.Normal;
            this.MainForm.Activate();
        }
    }
}

Answer 2

为了添加Hans Passant写的内容，我在主窗体上添加了一个额外的方法来处理恢复窗口并激活窗口。这是为了包装表单的调用所需条件。

因此，表单上添加的方法是：

/// <summary>
/// Recovers this instance of the form.
/// </summary>
public void RestoreFromTray()
{
   if(this.InvokeRequired)
   {
      this.Invoke(new Action(RestoreFromTray) );
      return;
   }
   this.Visible = true;
   this.WindowState = FormWindowState.Normal;
   this.Activate();
}

然后在汉斯＆＃39;方法，我将覆盖更改为：

protected override void OnStartupNextInstance(StartupNextInstanceEventArgs eventArgs) 
{
    ((formClassName)this.MainForm).RestoreFromTray();
}

其中formClassName是表单的类名。

运行一个程序实例

2 个答案: