ios归档

归档好比java中的序列化反序列化，即把内存中对象保存到硬盘中，同时可以把硬盘中对象读入内存
        
         自定义类需要实现<NSCoding>协议并实现- (void)encodeWithCoder:(NSCoder *)coder 和 - (id)initWithCoder:(NSCoder *)coder才能被归档，

归档可以自动实现深复制

//
//  main.m
//  bundle
//
//  Created by Young on 15/10/12.
//  Copyright (c) 2015年 Young. All rights reserved.
//

#import <Foundation/Foundation.h>


@interface MyData : NSObject<NSCoding>

@property NSString* color;
@property double weight;
@property int size;

@end

@implementation MyData

- (void)encodeWithCoder:(NSCoder *)coder
{
    [coder encodeObject:_color forKey:@"color"];
    [coder encodeDouble:_weight forKey:@"weight"];
    [coder encodeInt:_size forKey:@"size"];
    
}


- (id)initWithCoder:(NSCoder *)coder
{
    
    _color=[coder decodeObjectForKey:@"color"];
    _weight=[coder decodeDoubleForKey:@"weight"];
    _size=[coder decodeIntForKey:@"size"];
    return self;
}
- (NSString *)description
{
    return [NSString stringWithFormat:@"color=%@, weight=%f, size=%d", _color,_weight,_size];
}
@end
int main(int argc, const char * argv[]) {
    @autoreleasepool {
 

    
    
        /*归档好比java中的序列化反序列化，即把内存中对象保存到硬盘中，同时可以把硬盘中对象读入内存
        
         自定义类需要实现<NSCoding>协议并实现- (void)encodeWithCoder:(NSCoder *)coder 和 - (id)initWithCoder:(NSCoder *)coder才能被归档，
        */
        NSArray* arr=@[@"abc",@"def",@"xyz"];
        
        [NSKeyedArchiver archiveRootObject:arr toFile:@"data.dat"];
        
        NSArray* a=[NSKeyedUnarchiver unarchiveObjectWithFile:@"data.dat"];
        
        NSLog(@"%@",a);
        
        
        MyData*dat=[MyData new];
        [dat setColor:@"red"];
        [dat setWeight:2.0];
        [dat setSize:10];
        
        
        [NSKeyedArchiver archiveRootObject:dat toFile:@"mydat"];
        dat=[NSKeyedUnarchiver unarchiveObjectWithFile:@"mydat"];
        NSLog(@"%@",dat);
        
        
        
        
        
//        可以使用NSData把多个对象一起归档
        
        NSDictionary* dic=@{@"a":@"1"
                            ,@"b":@"2"
                            ,@"c":@"3"
                            };
        
        NSMutableData* mulData=[NSMutableData data];
        //用NSMutableData初始化NSKeyedArchiver
        NSKeyedArchiver* mulKA=[[NSKeyedArchiver alloc]initForWritingWithMutableData:mulData];
        
        [mulKA encodeObject:arr forKey:@"arr"];
        [mulKA encodeObject:dic forKey:@"dic"];
        [mulKA encodeObject:dat forKey:@"mydata"];
        [mulKA encodeObject:@"string..." forKey:@"str"];
        //调用finishEncoding完成归档
        [mulKA finishEncoding];
        //保存到mulData.dat文件中
        if ([mulData writeToFile:@"mulData.dat" atomically:YES]==NO) {
            NSLog(@"归档失败");
        }else
            NSLog(@"归档成功");
        
        //////
        //从mulData.dat文件中归档
        NSData*data=[NSData dataWithContentsOfFile:@"mulData.dat"];
        NSKeyedUnarchiver* nskn=[[NSKeyedUnarchiver alloc]initForReadingWithData:data];
        
        arr=[nskn decodeObjectForKey:@"arr"];
        dic=[nskn decodeObjectForKey:@"dic"];
        dat=[nskn decodeObjectForKey:@"mydata"];
        NSString* s=[nskn decodeObjectForKey:@"str"];
        
        //调用finishDecoding完成归档
        [nskn finishDecoding];
        
        NSLog(@"decodeObject   %@  \n%@ \n  %@ \n  %@",arr,dic,dat,s);
        
    }
    return 0;
}

打印如下

2015-10-12 12:41:50.765 bundle[1426:101541] (
    abc,
    def,
    xyz
)
2015-10-12 12:41:50.769 bundle[1426:101541] color=red, weight=2.000000, size=10
2015-10-12 12:41:50.772 bundle[1426:101541] 归档成功
2015-10-12 12:41:50.773 bundle[1426:101541] decodeObject   (
    abc,
    def,
    xyz
)  
{
    a = 1;
    b = 2;
    c = 3;
} 
  color=red, weight=2.000000, size=10 
  string...