Questions and Answers
C# classes always contain a Main() method.
False
An object is an instantiation of a class.
True
The data components of a class often are its instance variables.
True
Declaring a class creates one object of a new data type.
Signup and view all the answers
After you declare a class, you must use the new operator to allocate memory for an object of that class and to instantiate it.
Signup and view all the answers
After an object has been instantiated, its public members can be accessed using the object's identifier, a dot, and a method call.
Signup and view all the answers
A property is a member of a class that defines how fields will be set and retrieved.
Signup and view all the answers
Properties contain set accessors for retrieving an object's fields and get accessors for setting the stored values.
Signup and view all the answers
You can create auto-implemented properties when you want a field's set accessor simply to assign a value to the appropriate field, and a field's get accessor simply to return the field value.
Signup and view all the answers
Good object-oriented techniques require that data should usually be hidden and access to it should be controlled by well-designed accessors.
Signup and view all the answers
Although private fields, methods, and accessors are the norm, occasionally you need to create public versions of them.
Signup and view all the answers
When you define a named constant within a class, it is always static; that is, the field belongs to the entire class, not to any particular instance of the class.
Signup and view all the answers
An implicit, or invisible, this reference is passed to every instance method and property accessor in a class; instance methods and properties are nonstatic.
Signup and view all the answers
You can explicitly refer to the this reference within an instance method or property.
Signup and view all the answers
Although the this reference exists in every instance method, it is invisible, so you can never refer to it within a method.
Signup and view all the answers
Every class you create is automatically supplied with a public constructor with no parameters.
Signup and view all the answers
If you write a constructor for a class, you do not have a default constructor for the class.
Signup and view all the answers
Any constructor you write must have the same name as its class, and constructors cannot have a return type.
Signup and view all the answers
Study Notes
C# Classes and Objects
- C# applications require a Main() method for execution, but not all classes must have one.
- An object represents an instantiation of a class, confirming the relationship between classes and objects.
- Instance variables serve as the data components within a class, storing essential information.
- Declaring a class sets up a new data type but does not create any instances of that class.
- To create an object from a class, the 'new' operator is necessary, as it allocates memory for the instance.
- Accessing public members of an instantiated object is done using the object's identifier followed by a dot and method call.
Properties in Classes
- A property in a class enables controlled access for setting and retrieving field values.
- Auto-implemented properties simplify the process of defining accessors for fields by automatically providing get and set methods.
Object-Oriented Principles
- Good practices in object-oriented programming emphasize encapsulation, advocating for data hiding and controlled access through accessors.
- Private fields and methods are conventional; public versions should be used selectively.
Constants and References
- Named constants in a class are static, indicating they belong to the class as a whole, not individual instances.
- Each instance method and property has an implicit 'this' reference, which is automatically accessible.
- It is possible to refer to 'this' explicitly within methods for clarity in code.
Constructors
- Every class has a public parameterless constructor by default unless a custom one is defined.
- Defining a constructor necessitates using the class name as its identifier, and constructors do not have return types.
- Creating a parameterless constructor causes it to replace the default constructor if only parameterless constructors exist; other constructors that require parameters remove the default.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your understanding of classes and objects in C# with this quiz. Each question explores fundamental concepts such as the Main() method, object instantiation, and instance variables. Perfect for students in ISDS 309 or anyone looking to brush up on their C# skills.
