从JSON /字典创建模型对象，而无需使用Objective-c运行时和硬编码或键

Question

I am trying to parse a JSON and create a Model(a nested class structure). I can do it using JSONModel (available on Github) but I do not want to use Obj-c Runtime.

Is there any other way to achieve this? Lets see what I did with some dummy code.

NSDictionary *dictionary = @{@"personalDetail":@{@"name":@"Anoop kumar vaidya",
                                                   @"dob":@"3 Aug 1981",
                                                   @"sex":@"Male"},
                             @"workDetail":@{@"current":@"Photon",
                                               @"y2014":@"TechM",
                                               @"y2012":@"Exilant",
                                               @"y2010":@"RSG"},
                             @"educationDetail":@{@"pg":@"Mca - 63%",
                                                    @"ug":@"Bca -63%",
                                                    @"s12":@"58%",
                                                    @"s10":@"66%"
                                                    }
                             };


self.model = [[MainModel alloc] initWithMainModel:dictionary];

Implementation of MainModel , here you see the keys are hard coded. I want to avoid it, to make it generic.

-(id)initWithMainModel:(NSDictionary *)dict{

    for (NSString *key in dict) {
        [self putValue:dict[key] forKey:key];
    }
    return self;
}


-(void)putValue:(NSDictionary *)value forKey:(NSString *)key{

    if ([key isEqualToString:@"personalDetail"]) { 
        self.personalDetail = [[Personal alloc] initWithDictionary:value];
    }
    else if ([key isEqualToString:@"workDetail"]){
        self.workDetail = [[Work alloc] initWithDictionary:value];
    }
    else if ([key isEqualToString:@"educationDetail"]){
        self.educationDetail = [[Education alloc] initWithDictionary:value];
    }
}

Implementation of Personal . Similarly other two classes, Work & Education are implemented.

-(id)initWithDictionary:(NSDictionary *)dict{

    for (NSString *key in dict) {
        [self putValue:dict[key] forKey:key];
    }
    return self;
}


-(void)putValue:(NSString *)value forKey:(NSString *)key{
    [self setValue:value forKey:key];
}

Answer 1

You can use the key and extract the class name of it. Then you get the class for this identifier witch NSClassFromString() to get the class and instantiate it with +alloc as usual:

key = …;
if ([key hasSuffix:@"Detail"]) 
{
  NSString *className = [key substringToIndex:[key length]-[@"Detail length]];
  className = [[[className substringToIndex:1] uppercaseString] stringByAppendingString:[className substringFromIndex:1]];
}

id instance = [[NSClassFromString( className ) alloc] initWithDictionary:…];

I said: You can do it this way. I did not say: You should .