iOS运行时归档与解档

相较于NSUserDefaults和NSFileManager，归档解档可以存储model模型。比如平时项目最常用的归档解档就是保存用户相关信息

1.新建一个基类MSModel

#import <Foundation/Foundation.h>

@interface MSModel : NSObject <NSCoding>

@end

#import "MSModel.h"
#import <objc/runtime.h>

@implementation MSModel

- (instancetype)initWithCoder:(NSCoder *)aDecoder {
    if (self = [super init]) {
        u_int count;
        objc_property_t *properties = class_copyPropertyList([self class], &count);
        for (int i = 0; i < count; i++) {
            const char *propertyName = property_getName(properties[i]);
            NSString *key = [NSString stringWithUTF8String:propertyName];
            [self setValue:[aDecoder decodeObjectForKey:key] forKey:key];
        }
        free(properties);
    }
    return self;
}

- (void)encodeWithCoder:(NSCoder *)aCoder {
    u_int count;
    objc_property_t *properties = class_copyPropertyList([self class], &count);
    for (int i = 0; i < count; i++) {
        const char *propertyName = property_getName(properties[i]);
        NSString *key = [NSString stringWithUTF8String:propertyName];
        [aCoder encodeObject:[self valueForKey:key] forKey:key];
    }
    free(properties);
}

@end

2.以后创建需要缓存的模型就继承自MSModel即可实现缓存的目的

#import "MSModel.h"

@interface CacheModel : MSModel

@property (nonatomic, copy, nullable) NSString *name;
@property (nonatomic, copy, nullable) NSString *ID;
@property (nonatomic, assign) NSInteger *age;
@property (nonatomic, assign) BOOL gender;

@end

3.在控制器中实现缓存

// 归档
CacheModel *model = [CacheModel new];
model.name = @"moses";
model.ID = @"10086";
model.age = 18;
model.gender = 1;
NSString *documentPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSString *filePath = [documentPath stringByAppendingPathComponent:@"cache001"];
[NSKeyedArchiver archiveRootObject:model toFile:filePath];

// 解档
NSString *documentPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject];
NSString *filePath = [documentPath stringByAppendingPathComponent:@"cache001"];
CacheModel *model = [NSKeyedUnarchiver unarchiveObjectWithFile:filePath];
NSLog(@"%@--%@--%d--%d", model.name, model.ID, model.age, model.gender);