C# Constructor

In C#, a constructor is a special method that is used to initialize an object of a class. The constructor is called when an instance of a class is created using the new keyword.

A constructor has the same name as the class and no return type, not even void.

Default Constructor

If a class does not have any constructor, C# provides a default constructor. The default constructor takes no parameters and does nothing.

1public class ExampleClass
2{
3    public ExampleClass()
4    {
5        // Default Constructor
6    }
7}

Parameterized Constructor

A constructor with parameters is called a parameterized constructor. The parameterized constructor is used to set the initial values of the class properties at the time of object creation.

1public class ExampleClass
2{
3    private string name;
4    private int age;
5
6    public ExampleClass(string name, int age)
7    {
8        this.name = name;
9        this.age = age;
10    }
11}

Constructor Overloading

In C#, it is possible to have multiple constructors with different parameters. This is called constructor overloading.

1public class ExampleClass
2{
3    private string name;
4    private int age;
5
6    public ExampleClass()
7    {
8        this.name = "";
9        this.age = 0;
10    }
11
12    public ExampleClass(string name, int age)
13    {
14        this.name = name;
15        this.age = age;
16    }
17}

Access Modifiers

The access modifiers such as public, private, protected can be used with constructors to control their access.

1public class ExampleClass
2{
3    private string name;
4    private int age;
5
6    public ExampleClass()
7    {
8        this.name = "";
9        this.age = 0;
10    }
11
12    public ExampleClass(string name, int age)
13    {
14        this.name = name;
15        this.age = age;
16    }
17
18    private ExampleClass(string name)
19    {
20        this.name = name;
21        this.age = 0;
22    }
23}

The above code defines two public constructors and a private constructor.