49c2c7164a
* Corrected enum code. Cannot declare: public enum phylum; Since this code will produce an error. If someone will copy the same code, it will not compile and run. I updated the code so that when someone will copy the code, it will not produce an error. * I also updated the spacing and tabbing on code. * Corrected the constructor DefineAnimal to Animal since the name of the class is Animal and DefineAnimal will produce an error. * Remove enum on parameter of constructor since this will produce an error. * Corrected class Dog as public enum breed will produce an error.
67 lines
2.1 KiB
Markdown
67 lines
2.1 KiB
Markdown
---
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title: Inheritance
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---
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# Inheritance
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Inheritance allows you to create a class that extends or modifies an existing class. This can be used to make classes that derive off of other classes.
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# Base class and Derived class
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These are the terms used for classes when referring to inheritance. The derived class inherits the base class, along with any variables, functions or processes that the base class uses. The derived class can then have its own variables and functions alongside the ones it inherits off the base class.
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For example, a Base class of 'Animal' can have a derived class of 'Dog'. The Animal class will contain features relating to animals in general, while the Dog class contains features unique to dogs. When the Dog class inherits the Animal class, it will be able to refer to both features relating to animals and features unique to dogs.
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# Rules of Inheritance
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Inheritance is one way. The base class does not inherit the features of the derived class.
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Inheritance is transitive. A Base class of 'Animal' can have a derived class of 'Dog' and this can have a derived class of 'Terrier'. The Terrier class will inherit both the features of the Dog class and the Animal class.
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C# does not support multiple inheritance. A class can only inherit from a single class.
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# The `:` symbol
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In C# the `:` symbol is used to denote inheritance. This is called when creating the derived class.
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## Example
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# Base class
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```
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public class Animal
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{
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public int ID;
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public string title;
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public enum phylum { };
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public enum dietType { };
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public phylum _phylum;
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public dietType _dietType;
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public Animal(int id, string name, phylum phylum, dietType diet)
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{
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this.ID = ID;
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this.title = name;
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this._phylum = phylum;
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this._dietType = diet;
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}
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}
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```
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# Derived class
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```
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public class Dog : Animal
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{
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public enum breed { };
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public int levelOfTraining;
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public void SayWoof()
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{
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Console.WriteLine("Woof");
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}
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}
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```
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<!--- To do - Constructor rules, Abstract, Sealing derived classes--->
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