In C#, do you need to call the base constructor?

Question

In C#, if I have an inherited class with a default constructor, do I have to explicitly call the base class' constructor or will it be implicitly called?

class BaseClass {     public BaseClass()     {         // ... some code     } } class MyClass : BaseClass {     public MyClass() // Do I need to put ": base()" here or is it implied?     {         // ... some code     } } 

Answer 1

You do not need to explicitly call the base constructor, it will be implicitly called.

Extend your example a little and create a Console Application and you can verify this behaviour for yourself:

using System;  namespace ConsoleApplication1 {     class Program     {         static void Main(string[] args)         {             MyClass foo = new MyClass();              Console.ReadLine();         }     }      class BaseClass     {         public BaseClass()         {             Console.WriteLine("BaseClass constructor called.");         }     }      class MyClass : BaseClass     {         public MyClass()         {             Console.WriteLine("MyClass constructor called.");         }     } } 

Answer 2

It is implied, provided it is parameterless. This is because you need to implement constructors that take values, see the code below for an example:

public class SuperClassEmptyCtor {     public SuperClassEmptyCtor()     {         // Default Ctor     } }  public class SubClassA : SuperClassEmptyCtor {     // No Ctor's this is fine since we have     // a default (empty ctor in the base) }  public class SuperClassCtor {     public SuperClassCtor(string value)     {         // Default Ctor     } }  public class SubClassB : SuperClassCtor {     // This fails because we need to satisfy     // the ctor for the base class. }  public class SubClassC : SuperClassCtor {     public SubClassC(string value) : base(value)     {         // make it easy and pipe the params         // straight to the base!     } }