What is the default constructor in C#?

A class constructor is a special member function of a class that is executed whenever we create new objects of that class. A default constructor does not have any parameter.

The following is an example showing how to work with default constructor in C# −

Example

 Live Demo

using System;

namespace LineApplication {
   class Line {
      private double length; // Length of a line

      public Line(double len) { //Parameterized constructor
      Console.WriteLine("Object is being created, length = {0}", len);
         length = len;
      }

      public void setLength( double len ) {
         length = len;
      }

      public double getLength() {
         return length;
      }

      static void Main(string[] args) {
         Line line = new Line(10.0);
         Console.WriteLine("Length of line : {0}", line.getLength());

         // set line length
         line.setLength(6.0);
         Console.WriteLine("Length of line : {0}", line.getLength());
         Console.ReadKey();
      }
   }
}

Output

Object is being created, length = 10
Length of line : 10
Length of line : 6