Objective-C-class (static) method, instance method, overwrite, and Property Review

First define a human parent class

Definition:

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////  Human.h//  OOP////  Created by jimmy.yang on 11-2-9.//  Copyright 2011 __MyCompanyName__. All rights reserved.// #import <Foundation/Foundation.h>@interface Human : NSObject {    BOOL sex;} +(void) toString; -(void) showSex; @end

Note: the plus sign before + (void) indicates that this is a class method (static method), and-(void) indicates that this is an instance method.

Implementation:

Note: The following-(ID) Init is the constructor. Correspondingly, there is also a-(void) dealloc method to release resources (similar to the Destructor or the dispose () method in C #)-note: the dealloc method will be detailed in memory management.

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////  Human.m//  OOP////  Created by jimmy.yang on 11-2-9.//  Copyright 2011 __MyCompanyName__. All rights reserved.// #import "Human.h"@implementation Human // Constructor-(id) init{    NSLog(@"init() in Human is called");    sex = TRUE;    return(self);} // Static method+ (void)toString{    NSLog(@"this is a class method of Human");}// Instance method- (void)showSex{    NSLog(@"my sex is %@",[email protected]"MALE":@"FEMALE");}@end

Define a woman subclass.

Definition:

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////  Woman.h//  OOP////  Created by jimmy.yang on 11-2-9.//  Copyright 2011 __MyCompanyName__. All rights reserved.// #import <Foundation/Foundation.h>#import "Human.h"@interface Woman : Human {    BOOL married;} -(void) canCook:(NSString*) foodName; -(void) setMarried:(BOOL)m; -(BOOL) Married; @end

Implementation:

Note the following: setmarried and married are standard attributes in obj-C (of course, other simplified attributes can be viewed later)

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////  Woman.m//  OOP////  Created by jimmy.yang on 11-2-9.//  Copyright 2011 __MyCompanyName__. All rights reserved.// #import "Woman.h"@implementation Woman // Woman class Constructor-(id) init{    NSLog(@"init() in Woman is called!");    if (self==[super init]){        sex = FALSE;        married = FALSE;    }    return (self);} // Overwrite tostring () in the parent class ()+(void)toString{    NSLog(@"This is Woman‘s ToString()");} // Woman can cook-(void)canCook:(NSString*) foodName{    NSLog(@"I can cook %@",foodName);} // Setter of the attribute-(void) setMarried:(BOOL)m{    married = m;} // Getter of the attribute-(BOOL) Married{    return married;} @end

Call in the main method:

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#import <Foundation/Foundation.h>#import "Human.h"#import "Woman.h" int main (int argc, const char * argv[]) {    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];     // insert code here...    NSLog(@"Hello, World!");         // Call the "static" method of the class    [Human toString];         NSLog(@"----------------");         // Create a human instance    Human *man = [Human new];         // Call man's showsex Method    [man showSex];         NSLog(@"----------------");         // Define a woman subclass instance    Woman *wife = [Woman new];    [wife canCook:@"Rice"];         // Call the method inherited from the parent class    [wife showSex];         // Set attributes    [wife setMarried:TRUE];         // Read the attribute value    NSLog(@"wife‘s married = %@",wife.Married==NO[email protected]"FALSE":@"TRUE");         NSLog(@"----------------");         // Call the tostring method after Overwrite    [Woman toString];              // Common methods in the factory mode, which are still applicable here (except that 'human 'may not respond to'-cancook: 'will be warned during compilation :')    Human *wife2 = [Woman new];    [wife2 canCook:@"soap"];                   NSLog(@"----------------");         [pool drain];    return 0;}

Running result:

17:01:02. 016 OOP [1725: a0f] Hello, world!
17:01:02. 053 OOP [1725: a0f] This is a class Method of Human
17:01:02. 062 OOP [1725: a0f] ----------------
17:01:02. 075 OOP [1725: a0f] Init () in human is called
17:01:02. 091 OOP [1725: a0f] My sex is male
17:01:02. 094 OOP [1725: a0f] ----------------
17:01:02. 099 OOP [1725: a0f] Init () in woman is called!
17:01:02. 104 OOP [1725: a0f] Init () in human is called
17:01:02. 105 OOP [1725: a0f] I can cook rice
17:01:02. 108 OOP [1725: a0f] My sex is female
17:01:02. 109 OOP [1725: a0f] Wife's married = true
17:01:02. 111 OOP [1725: a0f] ----------------
17:01:02. 116 OOP [1725: a0f] This is woman's tostring ()
17:01:02. 120 OOP [1725: a0f] Init () in woman is called!
17:01:02. 121 OOP [1725: a0f] Init () in human is called
17:01:02. 123 OOP [1725: a0f] I can cook soap
17:01:02. 125 OOP [1725: a0f] ----------------