The method of calling a class or instance (object) of a specific language in oc language is called sending a message or calling a method.

There are two kinds of method calls in oc:

The first kind:

Class name or object name method name;

[example method];

[ClassOrInstance method: arg1];

[class or instance method 1:arg 2 method 2:arg 2]；

The second type:

Object name. Method name; (point grammar)

[[class or instance method:arg 1]other method]； //Nested sending message