C#

//--This is an external assembly project (.dll)
namespace Foo
{
    [Serializable]
    public class Foo
    {
        Thread workThread_;

        public void Initialize()
        {
            workThread_ = new Thread(new ThreadStart(DoWork));
            workThread_.Start();
        }

        public void DoWork()
        {
            int i = 0;

            while (i < 500)
                i++;

            throw new Exception("Unhandled exception");
        }
    }
}

namespace AppDomainTest
{
    public class Bar
    {

        AppDomain new_domain;

        public Bar()
        {
           
        }

        private void new_domain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
        {
           //--Cleanup new_domain and dispose it
            new_domain = null;
	    
	    //--After this event handler finishes so the main application process finishes although the event handler is subsrcibed on foo_test
        }

        public void InitializeBar()
        {
            Foo.Foo foo_test;

            new_domain = AppDomain.CreateDomain("Auxilary domain");
            foo_test = (Foo.Foo)new_domain.CreateInstanceFromAndUnwrap("Foo.dll", "Foo.Foo");
            
            new_domain.UnhandledException += new UnhandledExceptionEventHandler(new_domain_UnhandledException);

            foo_test.Initialize();
        }
    }
}

 using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Services;

//sql client import

using System.Data.SqlClient;
using System.Data;

using System.Data.OleDb;

namespace WebService1
{
    /// <summary>
    /// Summary description for Service1
    /// </summary>
    //[WebService(Namespace = "http://tempuri.org/")]
    //[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
    //[System.ComponentModel.ToolboxItem(false)]
    // To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line. 
    // [System.Web.Script.Services.ScriptService]
    public class Service1 : System.Web.Services.WebService
    {

        

        
        

        [WebMethod]
        public DataTable getData()
        {
            OleDbConnection con = new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\\MemberSites\\MemberSites_AspSpider_Info\\akosiDAN\\database\\Database1.mdb");
            DataSet ds = new DataSet();
            DataTable dt = new DataTable();
            ds.Tables.Add(dt);

            OleDbDataAdapter da = new OleDbDataAdapter ("Select * from phonebooktable",con);
            da.Fill (dt);

            return dt;
        }

        [WebMethod]
        public DataTable getData()
        {
            SqlConnection con = new SqlConnection("server= DANDAN-PC\\SQLEXPRESS;uid=MYID;pwd=MYPASSWORD;database=phonebookdatabase");
            DataSet ds = new DataSet();
            DataTable dt = new DataTable();
            ds.Tables.Add(dt);

            SqlDataAdapter da = new SqlDataAdapter("Select * from phonebooktable", con);

            da.Fill(dt);

            return dt;
        }
    }
}