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C#

Pratham Patel
Pratham Patel
4,976 Points
Posted by Pratham Patel
Pratham Patel
4,976 Points

In C# object oriented programming when you create an instance and you give it a data type do you use the classes name as

When you create an instance of a class is the type the same as the classes name

2 Answers

tjgrist
tjgrist
6,553 Points
tjgrist
tjgrist
6,553 Points

Yes, when you create an instance of a class (also known as an object), the type should be the same as the classes name. This is because classes are simply other data types. All classes are data types. For example, string is a class and therefore a data type. Int is a class, and therefore a data type. A List is a class, and therefore a data type. Make sense?

So, say you have a class called "Student". When you want to instantiate a new student, you want it to be of class Student, which is the same as saying you want it to be of type Student. So, you say something like:

Student newStudent = new Student();
Ryan Sheppard
Ryan Sheppard
2,866 Points
Ryan Sheppard
Ryan Sheppard
2,866 Points

While this is a good general-rule-of-thumb for beginners, it's worth pointing out instance type name and assignment type name won't necessarily always be the same if:

  • The instance type is an interface implemented by the assignment type
// Apple implements IFruit
IFruit fruit = new Apple();
  • The instance type is a parent class of the assignment type
// Apple inherits from Fruit
Fruit fruit = new Apple();
tjgrist
tjgrist
6,553 Points

Yes Ryan, I was debating whether or not to include those concepts here... chose not to ;)