Calling the base class constructor C# with Example

A constructor of a base class is called before a constructor of a derived class is executed. For example, if Mammal 
extends Animal, then the code contained in the constructor of Animal is called first when creating an instance of a 
Mammal. 
If a derived class doesn't explicitly specify which constructor of the base class should be called, the compiler 
assumes the parameterless constructor. 
public class Animal 
{ 
public Animal() { Console.WriteLine("An unknown animal gets born."); } 
public Animal(string name) { Console.WriteLine(name + " gets born"); } 
} 
public class Mammal : Animal 
{ 
public Mammal(string name) 
{ 
Console.WriteLine(name + " is a mammal."); 
} 
} 
In this case, instantiating a Mammal by calling new Mammal("George the Cat") will print 
An unknown animal gets born. 
George the Cat is a mammal. 
 

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Calling a different constructor of the base class is done by placing : base(args) between the constructor's 
signature and its body: 
public class Mammal : Animal 
{ 
public Mammal(string name) : base(name) 
{ 
Console.WriteLine(name + " is a mammal."); 
} 
} 
Calling new Mammal("George the Cat") will now print: 
George the Cat gets born. 
George the Cat is a mammal. 
View Demo