OBJECTIVE-C Features

1. Compatibility

OC is an object-oriented C language that can have C and C + + statements in OC Code, which can call C functions or access methods through C + + objects.

2. String

OC usually does not use a C language style string. Most of the cases (strings in corefoundation are C languages) are strings of type NSString that use the foundation framework. The NSString class provides a class wrapper for strings, supports Unicode, printf-style formatting tools, and so on. It is placed before the ordinary double-quoted string with an @ symbol. such as: NSString *mystring = @ "LJSDFJSDLKFJ";

Framework: Like a package in Java.

Method: Necessarily a class or an object, that is, it must have a body. It is used in object-oriented languages.

Function: Used in a process-oriented language, it has no subject.

But in objective-c, methods and functions are available. such as: NSLog (), it has no subject, so it is a method.

3. Class

Objective-c is an object-oriented language, and defining a class is its basic ability.

The class declaration and implementation of OBJECTIVE-C consists of two parts: the interface part and the implementation part.

4. Methods

Objective-c is an object-oriented language, and the definition method is its basic ability.

The method in Objective-c is not "." Operators, instead of the "" "operator. Sometimes a method call is also called: a message is sent.

5. Properties

The Objective-c property is the concept proposed by the 2.0, which is a means of substituting the "Read method (getter)" and "Set Method (Setter)" For access to member variables (the property is instead the setter and getter method, plainly). In order to encapsulate a class, it is generally not directly accessible to member variables, but through property access.

6. Agreement

The protocol in OBJECTIVE-C is similar to an interface in Java or a pure virtual class of C + +, except that there is no implementation part of the interface Definition section, that is, only h files do not have m files.

7. Classification

The classification in OBJECTIVE-C is similar to the inheritance mechanism by which the functions of the parent class can be extended.

OBJECTIVE-C Features