归档：将对象类型转换成数据类型，以文件形式存储，如果想读取归档中的数据，可以通过反归档形式，还原数据
归档三种形式
1.将Foundation框架中对象进行归档
2.对自定义内容进行归档
3.自定义类对象进行归档

一、新建类Person

/*
 1.首先：复杂对象所属的类必须遵循<NSCoding>
 - (void)encodeWithCoder:(NSCoder *)aCoder;//序列化
 - (nullable instancetype)initWithCoder:(NSCoder *)aDecoder;//反序列化
*/

Person.h文件

#import <Foundation/Foundation.h>

@interface Person : NSObject<NSCopying>

@property(nonatomic,strong)NSString *name;

@property(nonatomic,strong)NSString *gender;

@property(nonatomic,assign)int age;

@end

Person.m文件

/*
 把对象转换为字节序列的过程称为对象的序列化。
 把字节序列恢复为对象的过程称为对象的反序列化。
 */
#import "Person.h"

@implementation Person

//归档(序列化)
//对person对象进行归档时，此方法执行
//对person中想要进行归档时的所有属性，进行序列化操作
- (void)encodeWithCoder:(NSCoder *)aCoder{
    [aCoder encodeObject:self.name forKey:@"name"];
    [aCoder encodeInt:self.age forKey:@"age"];
}
//反归档(反序列化)
//对person进行反归档时，该方法执行
//创建一个新的person对象，所有属性通过反序列化得到
- (nullable instancetype)initWithCoder:(NSCoder *)aDecoder{
    if (self = [self init]) {
        self.name = [aDecoder decodeObjectForKey:@"name"];
        self.age = [aDecoder decodeIntForKey:@"age"];
    }
    return self;
}
@end

二、新建PCH File文件，并配置

//PrefixHeader.h
//在build Settings中搜索prefix，并配置绝对路径
//$(SRCROOT)/placeOnFile/PrefixHeader.pch
#ifndef PrefixHeader_pch
#define PrefixHeader_pch

#import "Person.h"

#endif

ViewController.m文件

#pragma mark --- Archiver
-(void)Archiver
{
    NSString *documentPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject];
    //Document文件夹下，创建新的文件
    NSString *filePath = [documentPath stringByAppendingPathComponent:@"customFile"];
    //1.使用Data对象进行归档
    NSMutableData *archiverData = [NSMutableData data];
    //2.创建归档对象
    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:archiverData];
    //归档数据
    [archiver encodeObject:@"小明" forKey:@"xm"];
    [archiver encodeObject:@[@"陈杨",@"高鞠",@"社会我楠哥"] forKey:@"name"];
    [archiver encodeInt:18 forKey:@"age"];
    //4.完成归档
    [archiver finishEncoding];
    //5.将归档写入
    BOOL result = [archiverData writeToFile:filePath atomically:YES];
    if (result) {
        NSLog(@"归档成功：%@",filePath);
    } else {
        NSLog(@"失败");
    }
    //反归档
    //拿到数据文件
    NSData *unarchiverData = [NSData dataWithContentsOfFile:filePath];
    //进行反归档
    NSKeyedUnarchiver *unarchver = [[NSKeyedUnarchiver alloc]initForReadingWithData:unarchiverData];
    NSString *stringData = [unarchver decodeObjectForKey:@"xm"];
    NSLog(@"%@, %@",stringData,filePath);
}
#pragma mark --- NSUserDefaults
-(void)writeNSUserDef
{
    /*
     NSUserDefaults是一个单例，只有这一个实例，可以用于数据永久储存
     可以储存：NSNumber,NSString,NSDate,NSArry...
     */
//    NSArray *array = @[@"banana",@"666",@"orange",@"apple"];
//    NSUserDefaults *user = [NSUserDefaults standardUserDefaults];
//    //存
//    [user setObject:array forKey:@"userArrays"];
//    //取
//    NSArray *arr = [user objectForKey:@"userArrays"];
//    NSLog(@"%@",arr);
    //注意： 要保证每一个key的唯一性，如果不唯一会覆盖
    //NSUserDefaults:存储对象不可变，如果存储对像可变，要将存储对象变为不可变
    NSMutableArray *mutableArray = [NSMutableArray arrayWithObjects:@"123",@"456",@"789", nil];
    NSArray *array1 = [NSArray arrayWithArray:mutableArray];
    //存储
    NSUserDefaults *user2 = [NSUserDefaults standardUserDefaults];
    [user2 setObject:array1 forKey:@"我是不可变的！"];
    //自定义数据类型
    Person *per = [Person new];
    per.name = @"国祥";
    per.gender = @"未知";
    per.age = 12;
    
    //创建存放person的数组
    NSMutableArray *dataArray = [NSMutableArray arrayWithCapacity:0];
    //将person类型转换成NSData类型
    NSData *data = [NSKeyedArchiver archivedDataWithRootObject:per];
    //将date存放到数组中
    [dataArray addObject:data];
    //创建
    NSUserDefaults *user = [NSUserDefaults standardUserDefaults];
    [user setObject:data forKey:@"person"];
    NSLog(@"%@",user);
    //取出数据
    NSUserDefaults *user3 = [NSUserDefaults standardUserDefaults];
    NSData *data1 = [user3 objectForKey:@"person"];
    Person *per1 = [NSKeyedUnarchiver unarchiveObjectWithData:data1];
    NSLog(@"%@",per1);
}

#pragma mark --- 复杂对象写入文件
-(void)archiver
{
    //$(SRCROOT)/placeOnFile/placeOnFile/PrefixHeader.pch
    Person *per = [Person new];
    per.gender = @"男";
    per.age = 18;
    NSString *path = NSHomeDirectory();
    NSLog(@"%@",path);
    path = [path stringByAppendingPathComponent:@"singeDog.txt"];
    //1.准备存储数据的对象
    NSMutableData *data = [NSMutableData data];
    //2.创建归档对象
    NSKeyedArchiver *archiver = [[NSKeyedArchiver alloc]initForWritingWithMutableData:data];
    //3.开始归档
    [archiver encodeObject:per forKey:@"person"];
    //4.完成归档
    [archiver finishEncoding];
    //5.写入到文件中
    BOOL result = [data writeToFile:path atomically:YES];
    if (result) {
        NSLog(@"归档成功：%@",path);
    }else{
        NSLog(@"归档失败");
    }
#pragma mark --- 反归档／反序列化／解码／
    //准备解档路径
    NSData *mydata = [NSData dataWithContentsOfFile:path];
    //创建反归档对象
    NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc]initForReadingWithData:mydata];
    //反归档
    Person *per1 = [Person new];
    per1 = [unarchiver decodeObjectForKey:@"person"];
    //完成反归档
    [unarchiver finishDecoding];
    //测试
    NSLog(@"%@",per1.name);
}