归档

来源：互联网发布：郎佐-鲍尔数据 nba 编辑：程序博客网时间：2024/04/28 05:15

归档也叫序列化，是将文件存在硬盘，解档是从硬盘还原

5种方式：

第一种、使用属性列表进行归档

如果对象是NSString，NSDictionary,NSArray,NSData或者NSNumber，可以使用writeToFile:atomically方法将数据写到文件,注意这种方式是明文

sample:

NSArray *array = @[@"abc",@"123",@23.4];

if ([array writeToFile:@"text.plist" atomically:YES])

{

NSLog(@"success");

}

NSArray *arr2=[NSArray arrayWithContentsOfFile:@"text.plist"];

NSLog(@"%@",arr2);

NSArray *array =[NSArray arrayWithObjects:

@"Hefeweizen", @"IPA", @"Pilsner", @"Stout",nil];

NSDictionary *dictionary =[NSDictionary dictionaryWithObjectsAndKeys:

array, @"array", @"Stout", @"dark", @"Hefeweizen", @"wheat", @"IPA"，

@"hoppy",nil];

// 得到documents directory的路径

NSString *arrPath = [NSHomeDirectory() stringByAppendingPathComponent:@"arr.plist"];

NSString *dicPath=[NSHomeDirectory() stringByAppendingPathComponent:@"dic.plist"];

// 保存array

[array writeToFile:arrPath atomically:YES];

// 保存dictionary

[dictionary writeToFile:dicPath atomically:YES];

// 从文件中读取回来

NSArray *arr=[NSArray arrayWithContentsOfFile:arrPath];

NSLog(@"arr is %@",arr);

NSDictionary *dic=[NSDictionary dictionaryWithContentsOfFile:dicPath];

NSLog(@"dic is %@",dic);

第二、NSKeyedArchiver--对象归档，数据会加密

1、对于NSArray或者NSDictionary sample code：

/***归档对象****/

NSArray *array = @[@"abc",@"123",@23.4];

NSString *homePath = NSHomeDirectory();

NSString *path = [homePath stringByAppendingPathComponent:@"test.arc"];

// BOOL success = [NSKeyedArchiver archiveRootObject:array toFile:path];

BOOL success=[NSKeyedArchiver archiveRootObject:array toFile:path];

if (success) {

NSLog(@"archive success");

}

/***解归档****/

NSArray *array2 =[NSKeyedUnarchiver unarchiveObjectWithFile:path];

NSLog(@"%@",array2);

结果：

success

2013-12-28 22:14:25.353 ArchiverDemo1[1206:303] (

abc,

123,

"23.4"

)

2、如果是其他类型的对象存储到文件，可以利用NSKeyedArchiver类创建带键的档案来完成

NSString *homePath = NSHomeDirectory();

NSString *path = [homePath stringByAppendingPathComponent:@"archiver2.archiv"];

NSMutableData *data = [NSMutableData data];

NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc] initForWritingWithMutableData:data];

NSArray *array = @[@"jack",@"tom"];

[archiver encodeInt:100 forKey:@"age"];

[archiver encodeObject:array forKey:@"names"];

[archiver finishEncoding];

[archiver release];

BOOL success = [data writeToFile:path atomically:YES];

if (success) {

NSLog(@"archive success");

}

/***解归档对象**/

NSData *data2 = [NSData dataWithContentsOfFile:path];

NSKeyedUnarchiver *unArchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data2];

int age = [unArchiver decodeIntForKey:@"age"];

NSArray *names = [unArchiver decodeObjectForKey:@"names"];

[unArchiver release];

NSLog(@"age=%d,names=%@",age,names);

3、自定义对象进行归档，需要实现归档协议NSCoding两个方法

对属性编码，归档的时候会调用

- (void)encodeWithCoder:(NSCoder *)aCoder

//对属性解码，解归档调用

- (id)initWithCoder:(NSCoder *)aDecoder

#import <Foundation/Foundation.h>

@interface user : NSObject <NSCoding>

@property(nonatomic,retain)NSString *name;

@property(nonatomic,retain)NSString *email;

@property(nonatomic,retain)NSString *pwd;

@property(nonatomic,assign)int age;

@end

#import "user.h"

#define AGE @"age"

#define NAME @"name"

#define EMAIL @"email"

#define PASSWORD @"password"

@implementation user

//对属性编码

- (void)encodeWithCoder:(NSCoder *)aCoder

{

[aCoder encodeInt:_ageforKey:@"age"];

[aCoder encodeObject:_nameforKey:AGE];

[aCoder encodeObject:_emailforKey:EMAIL];

[aCoder encodeObject:_pwdforKey:PASSWORD];

}

//对属性解码

- (id)initWithCoder:(NSCoder *)aDecoder

{

self=[super init];

if(self)

{

self.age=[aDecoderdecodeIntForKey:AGE];

self.name=[aDecoderdecodeObjectForKey:NAME];

self.email=[aDecoderdecodeObjectForKey:EMAIL];

self.pwd=[aDecoderdecodeObjectForKey:PASSWORD];

}

return self;

}

@end

第三种：NSUserDefaults sample code:
[[NSUserDefaults standardUserDefaults] setObject:authData forKey:@"SinaWeiboAuthData"]; [[NSUserDefaults standardUserDefaults] synchronize];
第四种、SQlite数据库、CoreData数据库

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