C#

/// Start the service
protected override void OnStart(string[] args)
{
    ServiceDesktopPermission();
}

/// Using Management Object services the option "Allow service to interact with desktop"
/// can be enabled. This gets unchecked/disabled each time a new install or update of the
/// service is performed.
static public void ServiceDesktopPermission()
{
   try
   {
	ConnectionOptions coOptions = new ConnectionOptions();
		
	coOptions.Impersonation = ImpersonationLevel.Impersonate;
		
	// CIMV2 is a namespace that contains all of the core OS and hardware classes.
	// CIM (Common Information Model) which is an industry standard for describing 
	//        data about applications and devices so that administrators and software 
	//        management programs can control applications and devices on different 
	//        platforms in the same way, ensuring interoperability across a network. 
			    
	ManagementScope mgmtScope = new ManagementScope(@"root\CIMV2", coOptions);
		
	mgmtScope.Connect();
		
	ManagementObject wmiService;

	wmiService = new ManagementObject("Win32_Service.Name='" + "My Service Name" + "'");
		
	ManagementBaseObject InParam = wmiService.GetMethodParameters("Change");
		
	InParam["DesktopInteract"] = true;
		
	wmiService.InvokeMethod("Change", InParam, null);
      }
   catch(Exception ex)
   {
     //TODO: Log this error
   }
}

MethodInfo addMethodInfo = fieldInfo.FieldType.GetMethod("Add");
object[] intValue = { 5 };
addMethodInfo.Invoke(tcObject, new Object[] { 5 });

    class ListElement
    {
        public ListElement()
        {
            m_element = 0;
        }

        public ListElement(int element)
        {
            m_element = 1;
        }

        public int m_element;
    }

    class TestClass
    {
        public int i = 0;

        public int IValue
        {
            get
            {
                return i;
            }
            set
            {
                i = value;
            }

        }
        public List<int> m_intList = new List<int>();
        public List<listelement> m_lstElement = new List<listelement>();
    }
    class Program
    {
        static void Main(string[] args)
        {
            TestClass tcObject = new TestClass();
            tcObject.i = 1;
            tcObject.m_intList.Add(1);
            tcObject.m_intList.Add(2);
            tcObject.m_lstElement.Add(new ListElement(1));

            // Following code modifies the field "I".
            {
                FieldInfo fieldInfo = tcObject.GetType().
                                        GetField(
                                        "i",
                                        BindingFlags.Static |
                                        BindingFlags.Instance |
                                        BindingFlags.NonPublic |
                                        BindingFlags.Public);

                fieldInfo.SetValue(tcObject, 2);

                System.Console.WriteLine("I value '{0}'", fieldInfo.GetValue(tcObject));
            }

            // Following code modifies the IValue property.
            {
                PropertyInfo propertyInfo = tcObject.GetType().
                                        GetProperty(
                                        "IValue",
                                        BindingFlags.Static |
                                    BindingFlags.Instance |
                                    BindingFlags.NonPublic |
                                    BindingFlags.Public);

                MethodInfo propertySetMethodInfo =
                                propertyInfo.GetSetMethod(true);

                propertySetMethodInfo.Invoke(tcObject, new Object[] { 3 });

                System.Console.WriteLine("Property IValue '{0}'", tcObject.i);
            }

            {
                FieldInfo fieldInfo = tcObject.GetType().
                                        GetField(
                                        "m_intList",
                                        BindingFlags.Static |
                                        BindingFlags.Instance |
                                        BindingFlags.NonPublic |
                                        BindingFlags.Public);

                MemberInfo[] listMemberInfoArray = tcObject.GetType().GetMember("m_intList");
                MemberInfo listMemberInfo = listMemberInfoArray[0];
                MethodInfo addMethodInfo = fieldInfo.FieldType.GetMethod("Add");
                object[] elementValue = { 5 };
                addMethodInfo.Invoke(fieldInfo.GetValue(tcObject), elementValue);

                foreach(int currElement in tcObject.m_intList)
                {
                    System.Console.WriteLine("INt List element {0}", currElement);
                }

                Console.WriteLine();
            }

            {
                FieldInfo fieldInfo = tcObject.GetType().
                                        GetField(
                                        "m_lstElement",
                                        BindingFlags.Static |
                                        BindingFlags.Instance |
                                        BindingFlags.NonPublic |
                                        BindingFlags.Public);

                MethodInfo addMethodInfo = fieldInfo.FieldType.GetMethod("Add");
                Object listElementObject = Activator.CreateInstance(fieldInfo.
                                                            FieldType.
                                                            GetGenericArguments()[0]);

                FieldInfo listElementFieldInfo = listElementObject.GetType().
                                        GetField(
                                        "m_element",
                                        BindingFlags.Static |
                                        BindingFlags.Instance |
                                        BindingFlags.NonPublic |
                                        BindingFlags.Public);

                listElementFieldInfo.SetValue(listElementObject, 2);

                object[] elementValue = { listElementObject };
                addMethodInfo.Invoke(fieldInfo.GetValue(tcObject), elementValue);


                foreach (ListElement currListElement in tcObject.m_lstElement)
                {
                    System.Console.WriteLine("List Item value '{0}'", currListElement.m_element);
                }
            }

        }
    }
</listelement></listelement></int></int>

Mycroft Holmes wrote:

ver 9 is VS 2008