Learn Access Modifiers in C#

Access modifiers in C# are keywords used to define the accessibility or visibility of classes, methods, variables, and other members. They help control how and where these members can be accessed. Here's a concise overview of the main access modifiers in C#:

1. Public

• Description: Accessible from anywhere in the program.
• Use Case: When you want a member to be universally accessible.
• Example

  public class MyClass
  {
      public int MyProperty { get; set; }
  }
  

2. Private

• Description: Accessible only within the containing class.
• Use Case: To encapsulate data and prevent external access.
• Example

  public class MyClass
  {
      private int myField;
  }
  

3. Protected

• Description: Accessible within the containing class and by derived classes.
• Use Case: When you want to allow access to subclasses but not to other classes.
• Example

  public class MyClass
  {
      protected int myField;
  }
  

4. Internal

• Description: Accessible only within the same assembly.
• Use Case: To restrict access to the same project or library.
• Example

  internal class MyClass
  {
      internal int MyProperty { get; set; }
  }
  

5. Protected Internal

• Description: Accessible within the same assembly or by derived classes in other assemblies.
• Use Case: A combination of protected and internal access.
• Example

  public class MyClass
  {
      protected internal int myField;
  }
  

6. Private Protected

• Description: Accessible within the containing class or derived classes in the same assembly.
• Use Case: To limit access to derived classes within the same assembly.
• Example

  public class MyClass
  {
      private protected int myField;
  }
  

Summary Table

Modifier	Same Class	Derived Class	Same Assembly	Other Assemblies
public	✔	✔	✔	✔
private	✔	✘	✘	✘
protected	✔	✔	✘	✘
internal	✔	✔	✔	✘
protected internal	✔	✔	✔	✔ (if derived)
private protected	✔	✔	✘	✘

These modifiers are essential for implementing encapsulation and controlling access to your code effectively.