iPhone开发【二十二】数据持久化小结之第3篇—归档（NSKeyedArchiver、NSKeyedUnarchiver）

iPhone开发【二十二】数据持久化总结之第3篇—归档（NSKeyedArchiver、NSKeyedUnarchiver）

转载请注明出处，原文网址：http://blog.csdn.net/m_changgong/article/details/8284135 作者：张燕广

实现的功能：1）演示使用归档持久化数据。

关键词：数据持久化 归档  NSKeyedArchiver NSKeyedUnarchiver

1、将上一篇

2、添加Person.h类，如下：

Person.h：

#import <Foundation/Foundation.h>@interface Person : NSObject<NSCoding,NSCopying> @property(nonatomic,retain)NSString *name;@property(nonatomic,retain)NSString *gender;@property(nonatomic,retain)NSString *age;@property(nonatomic,retain)NSString *education;@end

Person.m：

#import "Person.h"#define kNameKey        @"name"#define kGenderKey      @"gender"#define kAgeKey         @"age"#define kEducationKey   @"education"@implementation Person@synthesize name,gender,age,education;#pragma mark -#pragma mark NSCoding-(void)encodeWithCoder:(NSCoder *)aCoder{//编码    [aCoder encodeObject:name forKey:kNameKey];    [aCoder encodeObject:gender forKey:kGenderKey];    [aCoder encodeObject:age forKey:kAgeKey];    [aCoder encodeObject:education forKey:kEducationKey];}-(id)initWithCoder:(NSCoder *)aDecoder{//解码    if(self == [super init]){        name = [[aDecoder decodeObjectForKey:kNameKey]retain];        gender = [[aDecoder decodeObjectForKey:kGenderKey]retain];        age = [[aDecoder decodeObjectForKey:kAgeKey]retain];        education = [[aDecoder decodeObjectForKey:kEducationKey]retain];    }    return self;}#pragma mark -#pragma mark NSCopying-(id)copyWithZone:(NSZone *)zone{    Person *person = [[[self class]allocWithZone:zone]init];    person.name = [[self.name copyWithZone:zone]autorelease];    person.gender = [[self.gender copyWithZone:zone]autorelease];    person.name = [[self.name copyWithZone:zone]autorelease];    person.name = [[self.name copyWithZone:zone]autorelease];    return person;}@end

3、接下来主要修改ViewController

ViewController.h，主要是修改了宏，如下：

//#define kFileName @"data.plist"#define kFileName @"archive"#define kDataKey @"Data"#import <UIKit/UIKit.h>@interface ViewController : UIViewController@property(nonatomic,retain)IBOutlet UITextField *name;@property(nonatomic,retain)IBOutlet UITextField *gender;@property(nonatomic,retain)IBOutlet UITextField *age;@property(nonatomic,retain)IBOutlet UITextField *education;-(NSString *)dataFilePath;-(void)applicationWillResignActive:(NSNotification *)nofication;@end

主要修改了ViewController.m，如下：

#import "ViewController.h"#import "Person.h"@implementation ViewController@synthesize name,gender,age,education;-(NSString *)dataFilePath{    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);    NSString *documentsDirectory = [paths objectAtIndex:0];    return [documentsDirectory stringByAppendingPathComponent:kFileName];}- (void)didReceiveMemoryWarning{    [super didReceiveMemoryWarning];    // Release any cached data, images, etc that aren't in use.}#pragma mark - View lifecycle- (void)viewDidLoad{// Do any additional setup after loading the view, typically from a nib.    NSString *filePath = [self dataFilePath];    NSLog(@"filePath=%@",filePath);        if([[NSFileManager defaultManager] fileExistsAtPath:filePath]){        //属性列表        /*        NSArray *array = [[NSArray alloc]initWithContentsOfFile:filePath];        name.text = [array objectAtIndex:0];        gender.text = [array objectAtIndex:1];        age.text = [array objectAtIndex:2];        education.text = [array objectAtIndex:3];                [array release];*/                NSData *data = [[NSMutableData alloc]initWithContentsOfFile:[self dataFilePath]];        NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:data];        Person *person = [unarchiver decodeObjectForKey:kDataKey];        [unarchiver finishDecoding];                name.text = person.name;        gender.text = person.gender;        age.text = person.age;        education.text = person.education;                [unarchiver release];        [data release];    }        UIApplication *app = [UIApplication sharedApplication];    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(applicationWillResignActive:) name:UIApplicationWillResignActiveNotification object:app];        [super viewDidLoad];}-(void)applicationWillResignActive:(NSNotification *)nofication{        //属性列表    /*    NSMutableArray *array = [[NSMutableArray alloc]init];    [array addObject:name.text];    [array addObject:gender.text];    [array addObject:age.text];    [array addObject:education.text];    [array writeToFile:[self dataFilePath] atomically:YES];    [array release];*/        Person *person = [[Person alloc]init];    person.name = name.text;    person.gender = gender.text;    person.age = age.text;    person.education = education.text;        NSMutableData *data = [[NSMutableData alloc]init];    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:data];    [archiver encodeObject:person forKey:kDataKey];    [archiver finishEncoding];        [data writeToFile:[self dataFilePath] atomically:YES];    [person release];    [archiver release];    [data release];}- (void)viewDidUnload{    [super viewDidUnload];    // Release any retained subviews of the main view.    // e.g. self.myOutlet = nil;    self.name = nil;    self.gender = nil;    self.age = nil;    self.education = nil;}-(void)dealloc{    [name release];    [gender release];    [age release];    [education release];}- (void)viewWillAppear:(BOOL)animated{    [super viewWillAppear:animated];}- (void)viewDidAppear:(BOOL)animated{    [super viewDidAppear:animated];}- (void)viewWillDisappear:(BOOL)animated{[super viewWillDisappear:animated];}- (void)viewDidDisappear:(BOOL)animated{[super viewDidDisappear:animated];}- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation{    // Return YES for supported orientations    return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);}@end

4、通过iPhone开发【二十】数据持久化总结之第1篇NSUserDefaults 可以知道保存数据archive文件的存储位置是：

 /Users/duobianxing/Library/Application Support/iPhone Simulator/5.0/Applications/F694104D-894D-4230-A01B-C62066B3DEC8/Documents

5、总结：

与属性列表相比，归档可以写入复杂的对象（Person类的实例）。

需要源码的网友请留言哦

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