The vassal of my vassal is not my vassal

Just a thumb rule - avoid creating a PropertyExpression using

public static MemberExpression Expression.Property(Expression expression, MethodInfo property)


Instead prefer

public static MemberExpression Expression.Property(Expression expression, PropertyInfo property)


Interview

I would like to ask the following questions/tasks on a technical interview.

1. Implement a singleton.
   Yes, kinda boring question. But I'll expect simple implementation, like follows:
   
   public class Singleton{
     private Singleton(){}
     public static Singleton Instance = new Singleton();
   }
   
   and nothing more. There is no words about laziness. Anything more complicated signals about over-engineering.
2. Implement (I)Disposable pattern. And after it - When does a type need a finalizer?
   Second part is simple, first part is not good without explanation. In this case I'll wait for
   
   protected virtual void Dispose(bool isDisposing)
   
    
3. ...to be continued

Equals vs Equals

Could you create an example, when System.Object.Equals(a,b) will return true and a.Equals(b)will return false? 


And moreover, why does your example works and what paradigm have you violated to achieve the result?

default(Type)

Just another stupid question. In C# there is a default keyword, that allows to get a default value for a given type - null for reference types and some defined value for value types. Actually, if T is value type, "default(T)" is equals to "new T()". This keyword works in compile time and a compiler will substitute it with corresponding value.
But how could I get a default value in runtime, when I have System.Type object?

PropertyInfo.SetValue()

Consider the following example.

We have a class named Foo:

class Foo
{
public int Bar{get;set;}
}



What is the result of the following code execution?


var property = typeof(Foo).GetProperty("Bar");
Foo foo = new Foo {Bar = 5};
property.SetValue(foo, null, null);
Console.WriteLine(foo.Bar);

Difference between reference type and value type

Consider the following example. You need to create a dynamic method with the following signature:

void SetValue(object instance, object value)
{
}



The method should set the given value to the specified property in the instance object. Property should be specified by its PropertyInfo.
Alas, Expressions in .NET 3.5 don't allow to create complex expressions and functors. So the solution is to use DynamicMethod from System.Reflection.Emit:

How to start dump analysis with WinDbg

Just a side note.

1. Open a dump of interest
2. Load SOS extensions by executing
   .loadby sos mscorwks
3. If you receive the error like "Failed to load data access DLL", check your symbol path with ".sympath" command. To set the correct sympath, use
   .sympath srv*c:\mycache*http://msdl.microsoft.com/download/symbols
   and then reload dlls with
   .cordll -ve -u -l