Adding example on inheritance.

Author: aubertc

source/code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/FMember.cs

@@ -0,0 +1,17 @@
+class FMember : Person{
+    public string Relationship;
+    public FMember(string relationP, string nameP){
+        // This implicitely calls
+        // Person()
+        // which exists to create first
+        // a person object.
+        Relationship = relationP;
+        // the following
+        // name = nameP;
+        // gives
+        // InheritanceAndAccessModifiers/FMember.cs(5,9): error CS0122: 'Person.name' is inaccessible due to its protection level
+        // so we have to use the public method instead:
+        SetName(nameP);
+
+    }
+}

source/code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/Person.cs

@@ -0,0 +1,7 @@
+public class Person{
+    private string name;
+    public string GetName(){return name;}
+    public Person(){}
+    public void SetName(string nameP){name = nameP;}
+}
+    

source/code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/Program.cs

@@ -0,0 +1,5 @@
+class Program{
+    public static void Main(){
+        FMember test = new FMember("Cousin", "Samuel");
+    }
+}

source/lectures/oop/inheritance.md

@@ -74,3 +74,16 @@ We could then obtain a code as follows:
 Note that `SetNOW` inside the no-args constructor actually calls a `SetNOW` method inside `Bike`, but since there is no such method, it fallback to the `SetNOW` method from the `Vehicle` class.
 If there was a `SetNOW` method in both the `Bike` and the `Vehicle` method, we could not force access to the `Vehicle` method^[Actually, we could, if you read [this post](https://stackoverflow.com/a/32562464), but it is considered bad practice.].
 -->
+
+## On Private and Public Methods and Attributes
+
+The following example tries to make it clear that `private` attributes *cannot* be accessed from classes inheriting.
+
+
+```{download="./code/projects/InheritanceAndAccessModifiers.zip"}
+!include code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/Person.cs
+```
+
+```{download="./code/projects/InheritanceAndAccessModifiers.zip"}
+!include code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/FMember.cs
+```