添加Microsoft.VisualBasic引用,头引用

using Microsoft.VisualBasic.ApplicationServices;

打开App.xaml.cs文件,将文件修改为如下

class Program    {        [STAThread]        static void Main(string[] args)        {            SingleInstanceApp a = new SingleInstanceApp();            a.Run(args);        }    }     /// 
    /// App.xaml 的交互逻辑    /// 
    public partial class App : System.Windows.Application    {        protected override void OnStartup(System.Windows.StartupEventArgs e)        {            base.OnStartup(e);            InitializeComponent();        }    }     public class SingleInstanceApp : WindowsFormsApplicationBase    {        App win = null;        public SingleInstanceApp()        {            this.IsSingleInstance = true;        }         protected override bool OnStartup(Microsoft.VisualBasic.ApplicationServices.StartupEventArgs eventArgs)        {            win = new App();            win.Run();            return false;        }         protected override void OnStartupNextInstance(StartupNextInstanceEventArgs eventArgs)        {            foreach (System.Windows.Window _win in win.Windows)            {                if (_win.Visibility == System.Windows.Visibility.Visible)                {                    _win.Activate();                }            }        }    }

编译下,vs会告知有2个入口函数,定位到App.g.cs的main函数,直接删除掉就可以了~~以上代码通用,无需修改任何东西..当然,要写入自己的个性需求则自己改~~