C# ClassesLesson 33Free preview

C# Interface

This lesson is part of C# · All levels

Summary

Interface defines a contract as a set of methods without storing data in it. A class can implement multiple interfaces at once, thus being a solution to the single inheritance limitations in C#. The interface also allows explicit implementation to control the method name so as not to penetrate the class.

Key points

Interface is defined by the keyword interface and is conventionally preceded by a capital I.
The class implements the interface using the colon mark and must fill out the entire method.
A class can implement multiple interfaces at once.
Since C#8, the interface can contain default methods that already contain code and get-only properties.
The interface doesn't have a field instance because it's meant to split contracts, not data.

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