App.xaml.cs

using System;
using System.Globalization;
using System.IO;
using System.Reflection;
using System.Windows;

namespace RunCat
{
    /// <summary>
    /// App.xaml 的交互逻辑
    /// </summary>
    public partial class App : Application
    {
        private static Assembly OnResolveAssembly(object sender, ResolveEventArgs args)
        {
            Assembly executingAssembly = Assembly.GetExecutingAssembly();
            var executingAssemblyName = executingAssembly.GetName();
            var resName = executingAssemblyName.Name + ".resources";

            AssemblyName assemblyName = new AssemblyName(args.Name); 
            string path = "";
            if (resName == assemblyName.Name)
            {
                path = executingAssemblyName.Name + ".g.resources"; ;
            }
            else if(assemblyName.CultureInfo != null)
            {
                path = assemblyName.Name + ".dll";
                if (assemblyName.CultureInfo.Equals(CultureInfo.InvariantCulture) == false)
                {
                    path = string.Format(@"{0}\{1}", assemblyName.CultureInfo, path);
                }
            }

            using (Stream stream = executingAssembly.GetManifestResourceStream(path))
            {
                if (stream == null)
                    return null;

                byte[] assemblyRawBytes = new byte[stream.Length];
                stream.Read(assemblyRawBytes, 0, assemblyRawBytes.Length);
                return Assembly.Load(assemblyRawBytes);
            }
        }

        System.Threading.Mutex procMutex;
        protected override void OnStartup(StartupEventArgs e)
        {
            base.OnStartup(e);
            AppDomain.CurrentDomain.AssemblyResolve += OnResolveAssembly;
            procMutex = new System.Threading.Mutex(true, "_RUNCAT_MUTEX", out var result);
            if (!result)
            {
                procMutex = null;
                System.Diagnostics.Process.GetCurrentProcess().Kill();
            }
            Exit += App_Exit;
        }

        private void App_Exit(object sender, ExitEventArgs e)
        {
            if(procMutex != null) procMutex.ReleaseMutex();
        }
    }
}