constructor calling in inheritance

Best Use of C# Constructors In Inheritance [How To]


//We have two classes, one is ClassA and other is ClassB, the ClassB inherit base class ClassA.
//If we make the object of child class ClassB then which class constructor called first?
namespace ConsoleNamespace
{
    class ClassA
    {
        public ClassA()
        {
            Console.WriteLine("ClassA::Constructor()");
        }
    }
    class ClassB : ClassA
    {
        public ClassB()
        {
            Console.WriteLine("ClassB::Constructor()");
        }
    }
    class Test
    {
        static void Main(string[] args)
        {
            ClassB a = new ClassB();
            Console.ReadLine();
        }
    }
}

The output is base class "ClassA" constructor called first. i.e. (ClassA::Constructor())



Example 2
//If child constructor is missing the parent constructor is called.
namespace ConsoleNamespace
{
    class ClassA
    {
        public ClassA()
        {
            Console.WriteLine("ClassA::Constructor()");
        }
    }
    class ClassB : ClassA
    {

    }
    class Test
    {
        static void Main(string[] args)
        {
            ClassB a = new ClassB();
            Console.ReadLine();
        }
    }
}

OutPut: ClassA::Constructor()

Example 3
//If parent constructor is missing the child constructor is called.
namespace ConsoleNamespace
{
    class ClassA
    {

    }
    class ClassB : ClassA
    {
        public ClassB()
        {
            Console.WriteLine("ClassB::Constructor()");
        }
    }
    class Test
    {
        static void Main(string[] args)
        {
            ClassB a = new ClassB();
            Console.ReadLine();
        }
    }
}


Output : ClassB::Constructor()


ANIL SINGH

Anil Singh is an author, tech blogger, and software programmer. Book writing, tech blogging is something do extra and Anil love doing it. For more detail, kindly refer to this link..
My Blogs - https://code-sample.com and https://code-sample.xyz
My Book1 - BEST SELLING ANGULAR BOOK (INCLUDING ALL VERSIONS 2, 4, 5, 6, 7)
My Book2 - ANGULAR 2 INTERVIEW QUESTIONS BOOK - Both Books are Available on WorldWide.

www.code-sample.com/. Powered by Blogger.