當(dāng)一個(gè)Model類的屬性很多的時(shí)候我們需要寫很多重復(fù)的代碼,因此我們就可以用runtime獲取所有的屬性

記住要導(dǎo)入 #import <objc/message.h>

1.序列化

//編碼
- (void)encodeWithCoder:(NSCoder *)aCoder {
    //一般寫法
//    [aCoder encodeObject:_name forKey:@"name"];
//    [aCoder encodeObject:@(_age) forKey:@"age"];
//    [aCoder encodeObject:_phone forKey:@"phone"];

    //runtime
    unsigned int count = 0;
    Ivar * ivars = class_copyIvarList([Person class], &count);//獲取所以屬性
    for (int i = 0; i< count; i++) {
        Ivar ivar = ivars[i];//屬性名稱
        const char * name = ivar_getName(ivar);
        NSString *key = [NSString stringWithUTF8String:name];//C-->OC
        id value = [self valueForKey:key];//取值
        [aCoder encodeObject:value forKey:key];
    }
    free(ivars);//釋放
}

2.反序列化

//反編碼
-(instancetype)initWithCoder:(NSCoder *)aDecoder{
    if (self = [super init]) {
        //一般寫法
//        self.name = [aDecoder decodeObjectForKey:@"name"];
//        self.phone = [aDecoder decodeObjectForKey:@"phone"];
//        self.age = [[aDecoder decodeObjectForKey:@"age"] intValue];
        //runtime
        unsigned int count = 0;
        Ivar * ivars = class_copyIvarList([Person class], &count);//獲取所以屬性
        for (int i = 0; i< count; i++) {
            Ivar ivar = ivars[i];//屬性名稱
            const char * name = ivar_getName(ivar);
            NSString *key = [NSString stringWithUTF8String:name];//C-->OC
            id value = [aDecoder decodeObjectForKey:key];//取值
            [self setValue:value forKey:key];//賦值
        }
        free(ivars);//釋放
        
    }
    return self;
}

使用

//歸檔
    Person *p1 = [[Person alloc]init];
    p1.name   =  @"SUN";
    p1.age    =  25;
    p1.phone =  @"110";
    [NSKeyedArchiver archiveRootObject:p1 toFile:[NSTemporaryDirectory() stringByAppendingPathComponent:@"person.data"]];
    //檢測(cè)是否歸檔成功
    BOOL result = [[NSFileManager defaultManager] fileExistsAtPath:[NSTemporaryDirectory() stringByAppendingPathComponent:@"person.data"]];
    if (result) {
        NSLog(@"歸檔OK");
    }else{
        NSLog(@"歸檔NO");
    }

網(wǎng)絡(luò)請(qǐng)求解析數(shù)據(jù)也經(jīng)常用到

當(dāng)然可以使用小碼哥的 MJExtension
[Person mj_objectWithKeyValues:dict];

-(instancetype)initWithDic:(NSDictionary *)dic{
    if (self = [super init]) {
        //一般寫法
//        self.name = dic[@"name"];
//        self.phone = dic[@"phone"];
//        self.age = [dic[@"age"] intValue];
        //runtime
        unsigned int count = 0;
        Ivar * ivars = class_copyIvarList([Person class], &count);//獲取所以屬性
        for (int i = 0; i< count; i++) {
            Ivar ivar = ivars[i];//屬性名稱
            const char * name = ivar_getName(ivar);
            NSString *key = [NSString stringWithUTF8String:name];//C-->OC
            id value = dic[[key substringFromIndex:1]];//取值
            [self setValue:value forKey:key];//賦值
        }
        free(ivars);//釋放
    }
    return self;
    
}

基本上所有類似重復(fù)的代碼都可以這種方式
Demo:https://github.com/Sunkangp/runtime