iOS 自定义对象及子类及模型套模型的拷贝、归档存储的通用代码

一、runtime实现通用copy

如果自定义类的子类,模型套模型你真的会copy吗,小心有坑。

copy需要自定义类继承NSCopying协议

#import <objc/runtime.h>

- (id)copyWithZone:(NSZone *)zone {
    
    id obj = [[[self class] allocWithZone:zone] init];
    Class class = [self class];
    while (class != [NSObject class]) {
        unsigned int count;
        Ivar *ivar = class_copyIvarList(class, &count);
        for (int i = 0; i < count; i++) {
            Ivar iv = ivar[i];
            const char *name = ivar_getName(iv);
            NSString *strName = [NSString stringWithUTF8String:name];
            //利用KVC取值
            id value = [[self valueForKey:strName] copy];//如果还套了模型也要copy呢
            [obj setValue:value forKey:strName];
        }
        free(ivar);
        
        class = class_getSuperclass(class);//记住还要遍历父类的属性呢
    }
    return obj;
}

二、runtime实现通用归档解档

归档解档需要自定义类继承NSCoding协议

#import <objc/runtime.h>

#pragma
mark - 归档、解档 - (void)encodeWithCoder:(NSCoder *)encoder { Class class = [self class]; while (class != [NSObject class]) { unsigned int count; Ivar *ivar = class_copyIvarList(class, &count); for (int i = 0; i < count; i++) { Ivar iv = ivar[i]; const char *name = ivar_getName(iv); NSString *strName = [NSString stringWithUTF8String:name]; //利用KVC取值 id value = [self valueForKey:strName]; [encoder encodeObject:value forKey:strName]; } free(ivar); class = class_getSuperclass(class);//记住还要遍历父类的属性呢 } } - (id)initWithCoder:(NSCoder *)decoder { self = [super init]; if (self) { Class class = [self class]; while (class != [NSObject class]) { unsigned int count = 0; //获取类中所有成员变量名 Ivar *ivar = class_copyIvarList(class, &count); for (int i = 0; i < count; i++) { Ivar iva = ivar[i]; const char *name = ivar_getName(iva); NSString *strName = [NSString stringWithUTF8String:name]; //进行解档取值 id value = [decoder decodeObjectForKey:strName]; //利用KVC对属性赋值 [self setValue:value forKey:strName]; } free(ivar); class = class_getSuperclass(class);//记住还要遍历父类的属性呢 } } return self; }

三、NSUserDefaults存储自定义对象

//1.自定义类继承NSCoding协议,并实现归档解档,前面介绍过了,不多说

//2.将自定义对象转NSData
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:student];

//3.存到NSUserDefaults
[[NSUserDefaults standardUserDefaults] setObject:data forKey:@"myStudent"];
[[NSUserDefaults standardUserDefaults] synchronize];//这句要写,很多人都忘了

//4.存数组,数组中包含自定义对象
[dataArray addObject:data];//这个data是第2步归档得到的data

//5.NSUserDefaults只能存不可变数组,不要忘了转换成不可变
NSArray * array = [NSArray arrayWithArray:dataArray];
[[NSUserDefaults standardUserDefaults] setObject:array forKey:@"students"];

四、NSUserDefaults中读取归档的自定义对象

NSData *data = [[NSUserDefaults standardUserDefaults] objectForKey:@"myStudent"];
Student *student = [NSKeyedUnarchiver unarchiveObjectWithData:data];

 

posted @ 2018-02-05 17:00  张林峰  阅读(1719)  评论(0编辑  收藏  举报