03 May 07 p135@Applied Microsoft .NET Framework Programming

all the structures are immediately derived from the System.ValueType type. System.ValueType is itself immediately derived from the System.Object type. By definition, all value types must be derived from ValueType.

if you want a reference to an instance of a value type, the instance must be boxed. Usually this happens because you have a value type and you want to pass it to a method that requires a reference type.

Equals must be reflexive; that is, x.Equals(x) must return true.
Equals must be symmetric; that is, x.Equals(y) must return the same value as y.Equals(x).
Equals must be transitive; that is, if x.Equals(y) returns true and y.Equals(z) returns true, then x.Equals(z) must also return true.
Equals must be consistent. Provided that there are no changes in the two values being compared, Equals should consistently return true or false.

There are only three different ways to implement Equals.
Implementing Equals for a Reference Type Whose Base Classes Don’t Override Object’s Equals
Implementing Equals for a Reference Type When One or More of Its Base Classes Overrides Object’s Equals
Implementing Equals for a Value Type

Events typically use a delegate field to maintain the set of registered listeners.

The accessibility modifiers indicate which types and members can be legally referenced from code. The predefined attributes fine-tune this accessibility and allow you to change a member’s semantics.

When creating an instance of a reference type, memory is allocated for the instance,the object’s overhead fields (method table pointer and SyncBlockIndex) are initialized, and the type’s instance constructor is called to set the initial state of the object.

Type constructors shouldn’t call a base type’s type constructor. Such a call isn’t necessary because none of a type’s static fields are shared or inherited from its base type.

By default, the CLR assumes that all method parameters are passed by value. When reference type objects are passed, the reference (or pointer) to the object is passed (by value) to the method. This means that the method can modify the object and the caller will see the change. For value type instances, a copy of the instance is passed to the method.This means that the method gets its own private copy of the value type and the instance in the caller isn’t affected.