Adding notes on protected members.

Author: Clément

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

@@ -13,15 +13,15 @@ public FMember(string relationP, string nameP)
     // which exists to create first
     // a person object.
     Relationship = relationP;
-    // the following
     // name = nameP;
-    // gives
-    // error CS0122: 'Person.name' is inaccessible due to its protection level
+    // would give
+    // 'Person.name' is inaccessible due to its protection level
     // so we have to use the public method instead:
     SetName(nameP);
-    // the following
     // NewName(nameP);
-    // gives
-    //  error CS0122: 'Person.NewName(string)' is inaccessible due to its protection level
+    // would give
+    // error CS0122: 'Person.NewName(string)' is inaccessible due to its protection level
+    nickName = "Unknown";
+    commonName = "Unknown";
   }
 }

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

@@ -1,14 +1,14 @@
 public class Person
 {
   private string name;
+  protected string nickName;
+  public string commonName;
 
   public string GetName()
   {
     return name;
   }
 
-  public Person() { }
-
   public void SetName(string nameP)
   {
     if (name == null)
@@ -21,8 +21,10 @@ public void SetName(string nameP)
     }
   }
 
-  private void NewName(string newnameP)
+  private void NewName(string newNameP)
   {
-    name = newnameP + $" (previous name: {name})";
+    name = newNameP + $" (previous name: {name})";
   }
+  
+  public Person() { }
 }

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

@@ -10,6 +10,16 @@ public static void Main()
     test1.SetName("Patty");
     Console.WriteLine(test1.GetName());
 
-    FMember test = new FMember("Cousin", "Samuel");
+    // test1.name = "Test";
+    // would give
+    // 'Person.name' is inaccessible due to its protection level
+
+    // test1.nickName = "Test";
+    // would give
+    // 'Person.nickName' is inaccessible due to its protection level
+
+    test1.commonName = "Test";
+    FMember test2 = new FMember("Cousin", "Samuel");
+    
   }
 }

source/diag/cla/FMember.txt

@@ -0,0 +1,16 @@
+Person <|-- FMember
+
+class Person{
+    - name: string
+    # nickName: string
+    + commonName: string
+    + GetName(): string
+    + SetName(nameP: string)
+    - NewName(newNameP)
+    + Person()
+}
+
+class FMember{
+    + relationShip: string
+    + FMember(relationP: string, nameP:string)
+}

source/lectures/oop/inheritance.md

@@ -75,9 +75,13 @@ Note that `SetNOW` inside the no-args constructor actually calls a `SetNOW` meth
 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
+## On Private, Public and Protected Methods and Attributes
 
-The following example tries to make it clear that `private` attributes *cannot* be accessed from classes inheriting.
+The following example tries to make it clear that 
+
+- `private` attributes *cannot* be accessed from classes inheriting, nor from e.g., `Main` methods manipulating objects,
+- `protected` attributes *can* be accessed from classes inheriting, but *cannot* be accessed from e.g., `Main` methods manipulating objects,
+- `public` attributes *can* be accessed from classes inheriting *and* from e.g., `Main` methods manipulating objects.
 
 ```{download="./code/projects/InheritanceAndAccessModifiers.zip"}
 !include code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/Person.cs
@@ -86,3 +90,12 @@ The following example tries to make it clear that `private` attributes *cannot*
 ```{download="./code/projects/InheritanceAndAccessModifiers.zip"}
 !include code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/FMember.cs
 ```
+
+```{download="./code/projects/InheritanceAndAccessModifiers.zip"}
+!include code/projects/InheritanceAndAccessModifiers/InheritanceAndAccessModifiers/Program.cs
+```
+
+
+Protected attributes and methods are denoted with the `#` sign in UML diagrams, as follows:
+
+!include diag/cla/FMember.md