How constructor chaining works in C Sharp (C#) - Quick Revision & Summary

Recall & Review

beginner

What is constructor chaining in C#?

Constructor chaining is a way to call one constructor from another constructor in the same class to reuse code and avoid duplication.

beginner

How do you call one constructor from another in C#?

You use the this keyword followed by parentheses with arguments inside the constructor definition.

beginner

Why is constructor chaining useful?

It helps avoid repeating code by letting constructors share common initialization logic, making code cleaner and easier to maintain.

intermediate

What happens if you don't use constructor chaining and repeat code?

You risk having inconsistent initialization and more bugs because changes must be made in multiple places.

beginner

Show a simple example of constructor chaining in C#.

Example:<br><pre>class Car {
  public string Model;
  public int Year;

  public Car() : this("Unknown", 0) {}

  public Car(string model, int year) {
    Model = model;
    Year = year;
  }
}</pre>

Which keyword is used for constructor chaining in C#?

A this

B base

C super

D self

The this keyword calls another constructor in the same class.

What is the main benefit of constructor chaining?

A Increase program speed

B Avoid code duplication

C Create multiple objects

D Change class inheritance

Constructor chaining helps reuse code and avoid repeating the same initialization.

In constructor chaining, where must the this call appear?

A As the first statement in the constructor

B Anywhere in the constructor

C At the end of the constructor

D Outside the constructor

The this call must be the first statement inside the constructor.

What happens if you chain constructors incorrectly?

A Program ignores chaining

B Program runs slower

C Compilation error

D Creates infinite loop

Incorrect chaining causes a compilation error because the syntax rules are strict.

Can constructor chaining call a constructor from a base class?

A No, constructors cannot call other constructors

B Yes, use <code>this</code> keyword

C Yes, use <code>super</code> keyword

D No, use <code>base</code> keyword for that

To call a base class constructor, use the base keyword, not this.

Explain how constructor chaining works in C# and why it is useful.

Think about how constructors can share code inside the same class.

Write a simple C# class with two constructors where one constructor calls the other using constructor chaining.

Remember the this keyword must be the first statement in the constructor.