C# Properties

Study Notes

A property is a member that provides a flexible mechanism to read, write, or compute the value of a private field.
Properties can be read-write, read-only, or write-only.
The set accessor takes a single implicit parameter named value but does not return any value.
Example: public int Age { set { age = value; } get { return age; }

Static members are accessed by the class name, not the instance name.
Non-static class should also define a static constructor if the class contains static members.

A static constructor is a special constructor that gets called before the first object of the class is created.
It is used to initialize any static data, or to perform a particular action that needs performed once only.
Rules for static constructors:
- A class can have only one static constructor (no constructor overloading)
- Static constructor can not have any parameter
- Static constructor can not have any access specifier
Example: static class T { static int id; static T() { id = 0; } }

The compiler will provide the default parameterless constructor.
A static constructor needs its class’ fields and properties to be static also to be able to initialize them.

The readonly keyword is a modifier that can be used on fields.
When a field declaration includes a readonly modifier, assignments to the fields introduced by the declaration can only occur as part of the declaration or in a constructor in the same class.

Static fields are shared by all members of a class and are independent of any instances.
Declare the field static to make it a static field.
Non-static field is called an instance field.
Example: public static double PI = 3.14159265358979;

Static methods are similar to functions in a procedural language.
Static methods don’t need any data from the class and operate on values passed as arguments.
Method parameters/variables can’t be static.
Example: public static double Sqrt(double d) { ... }