Private and Public Instance Data in a Class

In a class, you can define public instance data, as fields.  Any instance of the class can read and write the instance data stored in these fields.

For example:

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public class Dog {     public string Name;     public int Age; }   // Creating a Dog object Dog kirby = new Dog(); kirby.Name = "Kirby"; kirby.Age = 14;

You might, however, want to declare some instance data that is visible from within the class’ methods, but not visible outside the class.  You can do this by declaring a field as private.

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public string Name; public int Age;   private DateTime lastPrint;   public void PrintName() {     Console.WriteLine(Name);       // lastPrint is visible here     lastPrint = DateTime.Now; }

This private field will not be visible from outside the class.

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Dog kirby = new Dog(); kirby.Name = "Kirby";   // Compiler error: inaccessible due to its protection level DateTime when = kirby.lastPrint;

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