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If I create two application domains and load the same assembly of same version. Would they be treated/isolated differently ?

I have created a new assembly named it as DyTest:-

using System;

namespace DyTest
{
    [Serializable]
    public sealed class Program
    {
        private static int _call = 0;
        public static int call()
        {
            _call += 1;
            return _call;
        }
    }
}

Build it and referenced it to console app. and call it as below:-

static void Main(string[] args)
        {
            CreateDomainAndDisplayValue("test1");
            CreateDomainAndDisplayValue("test2");
            Console.ReadLine();
        }

        static void CreateDomainAndDisplayValue(string domainName)
        {
            AppDomainSetup domaininfo = new AppDomainSetup();
            domaininfo.ApplicationBase = "D:\\Test\\CN_TEST\\CN_TEST\\bin\\Debug\\";
            Evidence adevidence = AppDomain.CurrentDomain.Evidence;

            AppDomain domain = AppDomain.CreateDomain(domainName, adevidence, domaininfo);

            var t = (domain.CreateInstanceAndUnwrap("DyTest, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null", "DyTest.Program")).GetType();

            MethodInfo m = t.GetMethod("call");
            object obj = Activator.CreateInstance(t);
            Console.WriteLine((int)m.Invoke(obj, new object[] { }));
        }

Now test1 is returning 1 Now test2 is returning 2

As variable _call is static variable, so it means either my understanding is not correct about Application Domains or I am missing something above.

I am expecting test1 should return 1 test2 should return 1

Can I achieve this by AppDomain?

Update 1 As referred here, I have changed the code as below:-

using System;

namespace DyTest
{
    public sealed class Program : MarshalByRefObject
    {
        private static int _call = 0;
        public static int call()
        {
            _call += 1;
            return _call;
        }
    }
}

Result:- Now test1 is returning 1 and test2` is returning 2

No difference.

Update 2 : got the solution from Eric's answer on this topic here

Modified method as follows :-

static void CreateDomainAndDisplayValue(string domainName)
        {
            AppDomainSetup domaininfo = new AppDomainSetup();
            domaininfo.ApplicationBase = "D:\\Test\\CN_TEST\\CN_TEST\\bin\\Debug\\";
            Evidence adevidence = AppDomain.CurrentDomain.Evidence;

            AppDomain domain = AppDomain.CreateDomain(domainName, adevidence, domaininfo);

            DyTest.Program objInstance = domain.CreateInstanceAndUnwrap("DyTest, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null", "DyTest.Program") as DyTest.Program;

            Console.WriteLine(objInstance.callFromEric());
        }

And 

using System;

namespace DyTest
{
    public sealed class Program : MarshalByRefObject
    {
        private static int _call = 0;
        public static int call()
        {
            _call += 1;
            return _call;
        }

        public int callFromEric()
        {
            return Program.call();
        }
    }
}

Output is 1 1

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    I believe it's answered already here: http://stackoverflow.com/questions/9806372/static-variable-instances-and-appdomains-what-is-happening – Denis Shulepov Sep 02 '14 at 15:24
  • another appdomain created the instance but you are invoking the method on a copy of it (because it's `Serializable`) in the main app domain. The result is as expected. – T McKeown Sep 02 '14 at 15:34
  • @TMcKeown I checked with by using `MarshalByRefObject` also results are same – vikas Sep 02 '14 at 15:54
  • @HansPassant the answer posted here http://stackoverflow.com/questions/9806372/static-variable-instances-and-appdomains-what-is-happening is not making any difference – vikas Sep 02 '14 at 16:07
  • @ErikPhilips I got the solution from your answer here http://stackoverflow.com/questions/4298913/static-fields-in-appdomain#4298979 . However, I still be interested in the explanation of the solution, I have mentioned above. – vikas Sep 02 '14 at 17:08

0 Answers0