SOLID PRINCIPLES TO MANAGE LARGE APPLICATIONS

Liskov Substitution Principle (LSP)

A quick intro to the Liskov Substitution Principle (LSP), why it’s important, and how to use it to validate object-oriented designs.

Adem Zeina
Jan 15 · 4 min read
Liskov Substitution Principle
Liskov Substitution Principle

Functions that use pointers of references to base classes must be able to use objects of derived classes without knowing it.

This principle states that, if S is a subtype of T, then objects of type T should be replaced with the objects of type S.

What’s a subtype?

Example without using the LSP in C#:

Example without using the LSP in C#
Example without using the LSP in C#
Example without using the LSP in C#
Example without using the LSP in C#

Example Using the Liskov Substitution Principle in C#

Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#

Another Example Using the Liskov Substitution Principle in C#

Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#
Example Using the Liskov Substitution Principle in C#

Robert Martin made the definition sound more smoothly and concisely:

Functions that use pointers of references to base classes must be able to use objects of derived classes without knowing it.

Liskov Substitution Principle
Liskov Substitution Principle
Liskov Substitution Principle
Liskov Substitution Principle

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Adem Zeina

Written by

Developer | Writer | Learner | Latest Business Technologies & Trends in a creative simplified way. Developer at DFDS

Dev Genius

Coding, Tutorials, News, UX, UI and much more related to development

Adem Zeina

Written by

Developer | Writer | Learner | Latest Business Technologies & Trends in a creative simplified way. Developer at DFDS

Dev Genius

Coding, Tutorials, News, UX, UI and much more related to development

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