Chapter 10Classes and Objects: A Deeper Look

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Classes

Classes are not just containers for methods◦ Virtually all are classes◦ Blueprint/Cookie Cutter/Recipe◦ Objects – instance of the class (new)◦ Type “prop” tab tab

OOP – vast topic

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10.2 Time Class Case Study

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Formatting: http://msdn.microsoft.com/en-us/library/dwhawy9k.aspxPadding: http://msdn.microsoft.com/en-us/library/txafckwd.aspx

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Classpublic Aprotected Binternal Cprivate D

Classpublic Aprotected B internal Cprivate D

SubClasspublic Aprotected Binternal Cprivate D

ASSEMBLY

SubClass (outside package)

public Aprotected B internal Cprivate D

Class (outside package)

public Aprotected B internal Cprivate D

Assembly is a chunk of precompiled code that can be executed by the .NET runtime environment. Usually, a .NET program consists of one or more assemblies

10.3 Controlling Access to Members

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10.4 Referring to the Current Object’s Members with the this Reference

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10.5 Time Class Case Study: Overloaded Constructors

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It's the marker for Inheritance and/or the constructor call chain.

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10.6 Default and Parameter-less Constructors

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10.7 Composition

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10.8 Garbage Collection and Destructors

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10.9 static Class Members

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static readonly field is set at run time, and can thus be modified by the containing class

the value of a const field is set to a compile time constant.

In the static readonly case, the containing class is allowed to modify it only in the variable declaration (through a variable initializer) in the static constructor (instance constructors, if it's not static)

static readonly is typically used if the type of the field is not allowed in a const declaration, or when the value is not known at compile time.

Instance readonly fields are also allowed. 

Remember that for reference types, in both cases (static and instance) the readonly modifier only prevents you from assigning a new reference to the field.  It specifically does not make immutable the object pointed to by the reference.

   

What is the difference between const and static readonly?

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10.10 readonly Instance Variables

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10.11 Data Abstraction and Encapsulation

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10.12 Class View and Object Browser

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