What is Constructor?

1 Answer

Answer :

A constructor is a special method whose task is to initialize the object of its class.
1. It is special because its name is the same as the class name
2. They do not have return types, not even void and therefore they cannot return values
3. They cannot be inherited, though a derived class can call the base class constructor
4. Constructor is invoked whenever an object of its associated class is created

Related questions

Description : What is Static Constructor?

Last Answer : In C# it is possible to write a static no-parameter constructor for a class. Such a class is executed once, when first object of class is created. Class MyClass { static MyClass() { //Initialization Code for static fields and properties. } }

Description : What is Interface?

Last Answer : An Interface is a group of constants and method declaration interface like classes, define a set of properties, methods, and events. But unlike classes, interfaces do not provide implementation

Description : How many types of Access Modifiers?

Last Answer : Public – Allows the members to be globally accessible. Private – Limits the member’s access to only the containing type. Protected – Limits the member’s access to the containing type and all classes derived from the containing type. Internal – Limits the member’s access to within the current project

Description : Whait is Method overriding?

Last Answer : Method overriding occurs when child class declares a method that has the same type arguments as a method declared by one of its superclass. By declaring base class function as virtual, we allow the function to be overridden in any of derived class

Description : What is a Method Overloading?

Last Answer : Method with same name but with different arguments is called method overloading

Description : What is Polymorphism?

Last Answer : Polymorphism means same operation may behave differently on different classes. Example : 1. Method Overloading and Method Overriding

Description : Is .NET C# supports Multiple inheritance?

Last Answer : Multiple inheritance of classes is not allowed in C#. but In C# you can implements more than one interface, thus multiple inheritance is achieved through interface

Description : Can you allow a class to be inherited, but prevent the method from being overridden?

Last Answer : Yes. Just leave the class public and make the method sealed

Description : Can you prevent your class from being inherited by another class?

Last Answer : Yes. The keyword “sealed” will prevent the class from being inherited.

Description : What are Sealed Classes in C#?

Last Answer : The sealed modifier is used to prevent derivation from a class

Description : What is an Inheritance?

Last Answer : The process of sub-classing a class to extend its functionality is called Inheritance. Advantage : It provides idea of reusability.

Description : What is ref keyword & out keyword?

Last Answer : Refrence Variable “must” be initialized before it is passed into a method.

Description : What is Value Type and Reference Type?

Last Answer : A variable is value type or reference type is solely determined by its data type. Ex: int, float, char, decimal, bool, decimal, struct, etc are value types As name suggest Reference Type stores reference to the ... ; Y = X; Console.writeline(Y.value); Y.value = 50; Console.writeline(X.value);

Description : What is Enumeration?

Last Answer : Enumeration improves code readability. It also helps in avoiding typing mistake

Description : What is a Garbage collection?

Last Answer : Garbage collection is the mechanism that reclaims the memory resources of an object when it is no longer referenced by a variable. And Net Runtime performs automatically performs garbage collection

Description : What is the difference between the destructor and the Finalize() method? When does the Finalize() method get called?

Last Answer : Finalize() corresponds to the .Net Framework and is part of the System.Object class. Destructors are C#'s implementation of the Finalize() method. The functionality of both Finalize() and the destructor is the same

Description : What is Destructor?

Last Answer : A destructor is just opposite to constructor. it has same as the class name, but with prefix ~ (tilde). They do not have return types

Description : What is Finalize() Method of Object class?

Last Answer : Each class in C# is automatically (implicitly) inherited from the Object class which contains a method Finalize(). This method is guaranteed to be called when your object is garbage collected

Description : What is Static Method of the class?

Last Answer : Methods that you can call directly without first creating an instance of a class. 1. As static methods may be called without any reference to object

Description : What is static member of a calss?

Last Answer : Static members belong to the whole class rather than to individual object Static members are accessed with the name of class rather than reference to objects

Description : Whar are properties?

Last Answer : Attribute of object is called properties Example:- A car has color as property.

Description : What is an encapsulation?

Last Answer : Wrapping up of data and function into a single unit is known as Encapsulation.

Description : What is an Object?

Last Answer : Instance of Class is called object. An object is created in memory using keyword “new”.

Description : What is a Class?

Last Answer : A user-defined data structure that groups properties and methods. Class doesn’t occupies memory.

Description : What is the role of constructor using default arguments?

Last Answer : A default constructor is any constructor that has no argumentsor where all required arguments are assigned default values. Thelatter provides a useful means of overloading a default constructorwithout incurring otherwise unnecessary code ... 0, double imaginary=0): re {real}, im{imaginary} {}// ...}

Description : How is the default constructor equivalent to a constructor having default arguments?

Last Answer : Any constructor that can be invoked without explicitly passingany arguments is a default constructor. Note that there can be onlyone default constructor so there can only be one ... combining two or moreconstructors into a single default constructor, thus reducingverbosity and code duplication.

Description : Who is known as the ‘Constructor of Modern France’?

Last Answer : Napoleon Bonaparte

Description : If a base class has a number of overloaded constructors, and an inheriting class has a number of overloaded constructors; can you enforce a call from an inherited constructor to a specific base constructor?

Last Answer : Yes, just place a colon, and then keyword base (parameter list to invoke the appropriate constructor) in the overloaded constructor definition inside the inherited class.

Description : Is constructor or destructor inheritance explicit or implicit? What does this mean?

Last Answer : Constructor or destructor inheritance is explicit…. Public Extended : base() this is called the constructor initializer.

Description : If I have a constructor with a parameter, do I need to explicitly create a default constructor?

Last Answer : Yes

Description : What is a constructor?

Last Answer : Answer:When we create instance of class a special method of that class, called that is constructor. Similarly, when the class is destroyed, the destructor method is called. These are general ... languages. It is initialized using the keyword New, and is destroyed using the keyword Finalize.

Description : If a base class has a number of overloaded constructors, and an inheriting class has a number of overloaded constructors; can you enforce a call from an inherited constructor to a specific base constructor?

Last Answer : Yes, just place a colon, and then keyword base (parameter list to invoke the appropriate constructor) in the overloaded constructor definition inside the inherited class.

Description : If a base class has a bunch of overloaded constructors, and an inherited class has another bunch of overloaded constructors, can you enforce a call from an inherited constructor to an arbitrary base constructor? 

Last Answer : Yes, just place a colon, and then keyword base (parameter list to invoke the appropriate constructor) in the overloaded constructor definition inside the inherited class. 

Description : C# provides a default constructor for me. I write a constructor that takes a string as a parameter, but want to keep the no parameter one. How many constructors should I write? 

Last Answer : Two. Once you write at least one constructor, C# cancels the freebie constructor, and now you have to write one yourself, even if there’s no implementation in it.

Description : Can a class have a static constructor?

Last Answer : Yes, a class can have a static constructor. Static constructors are called automatically, immediately before any static fields are accessed, and are generally used to initialize static class ... are referenced. Static constructors are called before instance constructors. An example is shown below.

Description : Does C# provide copy constructor?

Last Answer : No, C# does not provide copy constructor.

Description : Are constructors inherited? Can a subclass call the parent's class constructor? When?

Last Answer : Ans. You cannot inherit a constructor. That is, you cannot create a instance of a subclass using a constructor of one of it's superclasses. One of the main reasons is because ... developer the ability to override a superclasses constructor you would erode the encapsulation abilities of the language.

Description : Does Java provides default copy constructor ?

Last Answer : Ans. No

Description : Does Constructor creates the object ?

Last Answer : Ans. New operator in Java creates objects. Constructor is the later step in object creation. Constructor's job is to initialize the members after the object has reserved memory for itself.

Description : What is super constructor?

Last Answer : A: It is a constructor which is used to call the constructor of the super class and hence initialize the data members of the super class from within the sub class.

Description : What is the similarity between a method and a constructor?

Last Answer : A: Below are some of the similarities: 1) Both of them are member methods of any class. 2) Both can be parameterised or non-parameterised. 3) Both can be overloaded.

Description : What is a copy constructor?

Last Answer : A: It is a constructor which takes object as parameter and copies the value of the instance variable of that object to another object (creates a copy of an object).

Description : What is a constructor?

Last Answer : A: It is a member function with the same name as that of a class and is automatically called for initializing the variables of an object.

Description : What is constructor ?Describe its special properties?

Last Answer : A constructor is a special method of class. which is invoked automatically , whenever an object of a class is created. It has the same name as its class and resides similar to a method. A constructor ... .  It can be overloaded.  It is automatically used to initialize the member of the object.

Description : What is a COPY CONSTRUCTOR and when is it called?

Last Answer : copy constructor is a method that accepts an object of the same class and copies it s data members to the object on the left part of assignement: class Point2D{ int x; int y; public int ... MyPoint.color = 345; Point2D AnotherPoint = Point2D( MyPoint ); // now AnotherPoint has color = 345

Description : Define a constructor - What it is and how it might be called

Last Answer : constructor is a member function of the class, with the name of the function being the same as the class name. It also specifies how the object should be initialized. Ways of calling constructor ... memory on stack, the default constructor is implicitly called. Point2D * pPoint = new Point2D();

Description : Virtual constructor: Constructors cannot be virtual. Declaring a constructor as a virtual function is a syntax error. Does c++ support multilevel and multiple inheritance?

Last Answer : Yes.

Description : A ……………. takes a reference to an object of the same class as itself as an argument. A) Reference constructor B) Copy Constructor C) Self Constructor

Last Answer : B) Copy Constructor

Description : Which of the following characteristics of constructor are true. i) They should be declared in the public section. ii) They are invoked automatically when the objects are created. iii) They do not have return type and void also. ... and v C) Only i, iii, iv and v D) All i, ii, iii, iv and v

Last Answer : D) All i, ii, iii, iv and v

Description : Automatic initialization of object is carried out using a special member function called ………… A) Friend B) Casting C) Reference Parameter D) Constructor

Last Answer : D) Constructor