OC Learning 01-Classes and objects

Object-Oriented Programming

Basic:

• Concept: Object class Package Polymorphism
• The main languages are C++,JAVA,OC

Process-oriented and object-oriented differences

	Process oriented	Object Oriented
Characteristics	Analysis steps, Implementing functions	Analyze problems to identify participation and draw objects and their role
Focuses on	Implementation features	Object design (refers to function)
Example	C language	Oc,c++,java

Basic code:

    //OC Print    NSLog(@"Lanou");//Nsinteger integer, cgfloat float, nsstring string    Nsintegeri = -;NSLog(@"i =%ld", i);CGFloatf =3.14;NSLog(@"F =%g", f);//OC string can be put in Chinese    NSString*str= @"Yo Yo";NSLog(@"%@", str);array of//OC    //As for loop traversal, traverse directly with NSLog    Nsarray*arr = @[@"1",@"2",@"3"];NSLog(@"%@", arr); for(Nsintegeri =0; I <3; i++) {NSLog(@"%@", Arr[i]); }

Classes and Object classes

• Classes and objects are the core of object-oriented programming
• A class is an abstraction that has the same characteristics and behavioral things.

Object

• Object is an instance of a class
• Class is the type of object

Definition of class in OC

• Define the class first, then create the object, and then use the object
• Definition has two parts, interface and implementation (note separate write)
• File:. h for the interface file,. m for the implementation file
  Interface

@interface Student : NSObject@end

Realize

// 对应的实现文件@implementation Student

Creating objects

• Any object takes up space
• Create objects in two steps
  
  • ① Allocating space
  • ② initialization
• Initialization

// 1.分配空间Student *stu = [Student alloc];// 2.初始化stu = [stu init];// 可以把上两个步骤合成一个语句Student *stu = [[Student alloc] init];

The self that is returned in initialization refers to the return of the completed

- (id)init{    _stuName = @"俊宝宝";    _stuSex = @"女";    _stuHobby = @"男";    20;    100;    returnself;}

Working with objects

    Student *stu = [[Student alloc] init];    [stu sayHi];

Instance variable operation

• Instance variables are initialized with only a small amount of setup, and later perfect
• The visibility of instance variables is divided into three types
  
  • @public Public
  • @private Private
  • @protected protected

@interface Student : NSObject{    // 成员变量的可见度    @public    // 成员变量,或实例变量    NSString// 名字    NSInteger _stuAge;  // 年龄    NSString *_stuSex;  // 性别    CGFloat _stuScore;  // 分数    NSString *_stuHobby;// 爱好}@end

Action Members

    // 操作成员变量    // 对象通过->来访问自己的成员变量    NSLog(@"%ld"-> _stuAge);    // 修改年龄    -> =100;    NSLog(@"%ld"-> _stuAge);    // 修改姓名,直接修改字符串直接赋值    -> = @"切克闹";    NSLog(@"%@"-> _stuName);

Note: the instance variable of the public adornment can be accessed directly using the

Part of the Code

Main.m

int main(int argc, const char * argv[]) {    // 通过手机的类,创建对象,并且对对象的成员变量进行修改    MobilePhone *mPhone = [[MobilePhone alloc] init];    mPhone -> _phoneBrand = @"samsung";    mPhone -> _phoneColor = @"白色";    mPhone -> _phoneModel = @"S100";    4800;    1080;    NSLog(@"品牌为%@,颜色:%@,型号:%@,价格:%ld,屏幕:%ld",mPhone->_phoneBrand,mPhone->_phoneColor,mPhone->_phoneModel,mPhone->_phonePrice,mPhone->_phoneSize);     0;}

MobilePhone.h

 @interface  mobilephone : nsobject   { @public  nsstring  *_phonebrand;    nsstring  *_phonemodel;    nsinteger  _phonesize;    nsstring  *_phonecolor; nsinteger  _phoneprice;} -(void ) buyphone;-(void ) call;-(void ) sendmessage;-(void ) surfinternet;-(void ) Watchvideo; //write a function to print all the information -(void ) Sayhi; @end   

Mobilephone.m

 @implementation mobilephone - (void) buyphone{NSLog(@"bought a cell phone.");} - (void) call{NSLog(@"Make a phone call.");} - (void) sendmessage{NSLog(@"sent a message.");} - (void) surfinternet{NSLog(@"on a net.");} - (void) watchvideo{NSLog(@"I saw a video.");}//Rewrite the phone's initialization method- (ID) init{_phonebrand = @"Apple"; _phonecolor = @"Red"; _phonemodel = @"S5"; _phoneprice =4000; _phonesize = the;return  Self;} - (void) sayhi{NSLog(@"%@,%@,%@,%ld,%ld,", _phonebrand,_phonecolor,_phonemodel,_phoneprice,_phonesize);}

This article summarizes the basic contents of today's study

Copyright NOTICE: This article for Bo Master original article, without Bo Master permission not reproduced.

OC Learning 01-Classes and objects