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在 .NET 4.6 的 AppDomain 中引发 AccessViolationException（或另一个损坏状态异常）时，如何防止整个应用程序（进程）崩溃？我的目标是在其 AppDomain 中包装一个第 3 方库（GdPicture.NET 条形码阅读器），它会根据 IIS 故障转储间歇性地使 IIS 工作进程崩溃。换句话说，我想将第 3 方库调用隔离在其自己的应用程序域中，这样它就可以在自身内部发生故障而不会导致整个网站停机。

在下面的示例代码中，如果我不使用 HandleProcessCorruptedStateExceptions 属性，我无法捕获在不同 AppDomain（在 ClassLibrary1.dll 中）中引发的 AccessViolationException（包装在 TargetInvocationException 中）。如果我装饰 HandleProcessCorruptedStateExceptions （仅适用于第二次 AppDomain 调用），主进程继续运行是否安全，还是进入不稳定状态？

具有两个项目（一个控制台应用程序和一个类库）的 Visual Studio 解决方案。

在此处输入图像描述

using System;
using System.Reflection;
using System.Runtime.ExceptionServices;
using System.Security;

namespace StackOverflowQuestion
{
    class Program
    {
        static void Main(string[] args)
        {
            new Tester().RunTest();
        }
    }

    class Tester
    {
        public void RunTest()
        {
            var myTestAppDomain = AppDomain.CreateDomain("My Test AppDomain");
            var loader = (Loader)myTestAppDomain.CreateInstanceAndUnwrap(typeof(Loader).Assembly.FullName, typeof(Loader).FullName);
            TestHandleProcessCorruptedStateExceptions(loader, myTestAppDomain);

            // how can I make sure process doesn't crash when AppDomain "My Test AppDomain" crashes
            Console.WriteLine("This won't be written to console unless [HandleProcessCorruptedStateExceptions] attribute is present...");

            // keep console window open
            Console.ReadKey();
        }

        // [HandleProcessCorruptedStateExceptions, SecurityCritical]
        private void TestHandleProcessCorruptedStateExceptions(Loader loader, AppDomain appDomain)
        {
            Console.WriteLine("Loading 3rd party lib ClassLibrary1.dll...");
            loader.LoadAssembly(@"..\..\..\ClassLibrary1\bin\debug\ClassLibrary1.dll");
            try
            {
                // executing static method in dummy 3rd party dll in a different app domain (named "My Test AppDomain")
                loader.ExecuteStaticMethod("ClassLibrary1.Class1", "DoStuff", DateTime.Now.ToShortDateString() + " " + DateTime.Now.ToLongTimeString());
            }
            catch (TargetInvocationException)
            {
                AppDomain.Unload(appDomain);
                Console.WriteLine("DoStuff failed. This won't be written to console  unless [HandleProcessCorruptedStateExceptions] attribute is present...");
            }
        }
    }

    class Loader : MarshalByRefObject
    {
        private Assembly _assembly;

        public void LoadAssembly(string path)
        {
            _assembly = Assembly.Load(AssemblyName.GetAssemblyName(path));
        }

        public object ExecuteStaticMethod(string typeName, string methodName, params object[] parameters)
        {
            var type = _assembly.GetType(typeName);
            // assume there is no overloads for simplicity
            var method = type.GetMethod(methodName, BindingFlags.Static | BindingFlags.Public);

            return method.Invoke(null, parameters);
        }
    }
}

这是 ClassLibrary1 项目中 Class1.cs 中的代码：

using System;
using System.Runtime.InteropServices;

namespace ClassLibrary1
{
    public class Class1
    {
        public static void DoStuff(string msg)
        {
            Console.WriteLine("Throwing AccessViolationException now...");

            // throw an AccessViolationException which cannot be caught in a try/catch block
            FakeAccessViolationException();

            Console.WriteLine("Class1.DoStuff: " + msg);
        }

        private static void FakeAccessViolationException()
        {
            var ptr = new IntPtr(42);
            Marshal.StructureToPtr(42, ptr, true);
        }
    }
}
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