C# Classes and Objects
Classes and Objects
You learned from the previous chapter that C# is an object-oriented programming language.
Everything in C# is associated with classes and objects, along with its attributes and methods. For example: in real life, a car is an object. The car has attributes, such as weight and color, and methods, such as drive and brake.
A Class is like an object constructor, or a "blueprint" for creating objects.
Create a Class
To create a class, use the class
keyword:
Create a class named "Car
" with a variable color
:
class Car
{
string color = "red";
}
When a variable is declared directly in a class, it is often referred to as a field (or attribute).
It is not required, but it is a good practice to start with an uppercase first letter when naming classes. Also, it is common that the name of the C# file and the class matches, as it makes our code organized. However it is not required (like in Java).
Create an Object
An object is created from a class. We have already created the class named
Car
,
so now we can use this to create objects.
To create an object of Car
,
specify the class name, followed by the object name, and use the keyword new
:
Example
Create an object called "myObj
" and use
it to print the value of
color
:
class Car
{
string color = "red";
static void Main(string[] args)
{
Car myObj = new Car();
Console.WriteLine(myObj.color);
}
}
Note that we use the dot syntax (.
) to access variables/fields inside a class (myObj.color
). You will learn more about
fields in the next chapter.