Class and Object de differences in iOS

Concepts of classes and objects

A class is an abstraction of the same kind of thing, which defines the static attributes (attributes) and dynamic properties (methods) that such an object should have.

An object is an instance of a class and is a concrete thing.

Classes and objects are abstract and concrete relationships.

A class is actually a data type, and its variables are objects.

Relationship between class and class--inheritance relationship

A is B

If this is the case, in the design process can be regarded as an inheritance relationship.

For example: Students and primary school pupils are also students, so students are the parents of pupils, pupils are children of the class.

OC and Object-oriented

The object is the core of the OC program. "Everything is Object" is the core idea in the procedure.

Class and Object de differences in iOS