Constructor In C#

In C#, a constructor is a special method that is called when an instance of a class is created. It is used to initialize the object's state.

Constructors are fundamental in object-oriented programming for setting up initial values and enforcing rules at the time of object creation.

Every time you create object , you call constructor as well.

 

Here are the key points about constructors in C#:

1. Name: A constructor has the same name as the class.
2. No Return Type: Constructors do not have a return type, not even void.
3. Default Constructor: If no constructor is defined, C# provides a default parameterless constructor.
4. Parameterized Constructor: You can define constructors that take parameters to initialize the object with specific values.
5. Overloading: Constructors can be overloaded, meaning you can have multiple constructors in the same class with different parameter lists.
6. Static Constructor: Used to initialize static members of a class. It is called once, before any instances of the class are created or any static members are referenced.
7. Copy Constructor: Creates a new object as a copy of an existing object.

 

Constructor Types :

1. Default Constructor
2. Parameterized Constructor
3. Static Constructor
4. Copy Constructor
5. Private Constructor
6. Constructor Chaining
7. Base Constructor

Accessibility:

• Constructors can have different access modifiers (public, private, protected, internal).
• A private constructor is used to restrict instantiation and can be used in singleton patterns.

 

Overloading:

• Constructors can be overloaded by defining multiple constructors with different parameters.
• This allows creating objects in different ways.

Chaining Constructors:

• A constructor can call another constructor in the same class using the this keyword.
• This helps in reusing constructor code and reducing redundancy.

 

 

Inheritance and Base Constructors:

• When a class inherits from a base class, the derived class can call a constructor of the base class using the base keyword.
• This ensures that the base class is properly initialized before the derived class.

 

Static Constructors:

• Static constructors cannot take parameters.
• They are called automatically to initialize the class before any static members are accessed.
• They are typically used to initialize static fields.

 

Exceptions in Constructors:

• Constructors can throw exceptions if initialization fails.
• It is important to handle such exceptions appropriately to avoid runtime errors.

 

No Inheritance for Constructors:

• Constructors are not inherited. Each class must define its own constructors.
• The derived class constructors can call base class constructors to ensure proper initialization.