There are 6 types of access modifiers in C#:
Private Public Protected Internal Protected Internal Private Protected
What is Access Modifier (Specifier) in C#? Private Access Modifiers in C# C# Public Access Modifiers Protected Access Modifiers in C# C# Internal Access Modifiers C# Constructor
We will learn about the main access modifiers in C# with program examples as explained below.
Private Access Modifiers in C#
When Private access modifier is attached to either a property or a method, it means that those members cannot be accessed from any external program.
Example of Private Access Modifier
Let’s take an example and see what happens when we use the private access modifier. Let’s modify the current code in our Tutorial.cs file. In the SetTutorial method, let’s change the public keyword to private.
Now let’s switchover to our Program.cs file. You will notice that there is a red squiggly line under the SetTutorial method. Since we have now declared the SetTutorial method as private in our Tutorial class, Visual Studio has detected this. It has told the user by highlighting it that now this method will not work from the Program.cs file.
C# Public Access Modifiers
When Public access modifier is attached to either a property or a method, it means that those members can be accessed from any external program. We have already seen this in our earlier examples.
Example of Public Access Modifier
Since we have defined our methods as public in the Tutorial class, they can be accessed from the Program.cs file.
Protected Access Modifiers in C#
When Protected access modifier is attached to either a property or a method, it means that those members can be accessed only by classes inherited from the current class. This will be explained in more detail in the Inheritance class.
C# Internal Access Modifiers
When an Internal access modifier is attached to either a property or a method, those members can be accessed only by an internal program but not by an external program.
C# Constructor
C# Constructors are used to initializing the values of class fields when their corresponding objects are created. A constructor is a method which has the same name as that of the class. If a constructor is defined in a class, then it will provide the first method which is called when an object is created. Suppose if we had a class called Employee. The constructor method would also be named as Employee(). The following key things need to be noted about constructor methods
The C# default access modifier for the constructor needs to be made as public. There should be no return type for the constructor method.
Example of C# Constructor
Let’s now see how we can incorporate the user of constructors in our code. We will use constructors to initialize the TutorialID and TutorialName fields to some default values when the object is created. Step 1) The first step is to create the constructor for our Tutorial class. In this step, we add the below code to the Tutorial.cs file.
Code Explanation:-
We first add a new method which has the same name as that of the class. Because it is the same name as the class, C# treats this as a constructor method. So now whenever the calling method creates an object of this class, this method will be called by default. In the Tutorial constructor, we are setting the value of TutorialID to 0 and TutorialName to “Default”. So whenever an object is created, these fields will always have these default values.
Now let’s switchover to our Program.cs file and just remove the line, which calls the SetTutorial method. This is because we want just to see how the constructor works.
Code Explanation:-
The first step is to create an object for the Tutorial class. This is done via the ‘new’ keyword. We use the GetTutorial method of the Tutorial class to get the TutorialName. This is then displayed to the console via the Console.WriteLine method.
If the above code is entered properly and the program is executed, the following output will be displayed. Output:
From the output, we can see that the constructor was indeed called and that the value of the TutorialName was set to “Default”. Note: Here the value “default” is fetched from the constructor.
Summary
C# Access Modifiers or Access Specifiers are used to define the visibility of a class property or method. When Private access modifier is attached to either a property or a method, it means that those members cannot be accessed from any external program. When Public access modifier is attached to either a property or a method, it means that those members can be accessed from any external program. When Protected access modifier is attached to either a property or a method, it means that those members can be accessed only by classes inherited from the current class. When an Internal access modifier is attached to either a property or a method, those members can be accessed only by an internal program but not by an external program. C# Constructors are used to initializing the values of class fields when their corresponding objects are created.
