iOS 使用coreData存贮页面的模型数据中的字典

我们使用coreData时候，会遇到较为复杂的数据类型的存贮，例如，我们要存一个模型，但是一个模型里面有个字典，这时候，我们该如何存贮呢
如图所示，一个对象中含有一个字典

我们实现一个公共的方法，将对象的所有属性都赋值给对应的coreData模型

id makeRemoteModelToCoreDataModel(id remoteModel,Class remoteDataClass,NSManagedObject *coreDataModel) {
    int i;
    unsigned int propertyCount = 0;
    objc_property_t *propertyList = class_copyPropertyList(remoteDataClass, &propertyCount);
    
    
    NSMutableArray *propertyNameList = [NSMutableArray array];
    for ( i=0; i < propertyCount; i++ ) {
        objc_property_t *thisProperty = propertyList + i;
        const char* propertyName = property_getName(*thisProperty);
        NSString *string = [NSString stringWithFormat:@"%s",propertyName];
        [propertyNameList addObject:string];
    }
    
    if (propertyNameList.count > 0) {
        [propertyNameList enumerateObjectsUsingBlock:^(NSString* key, NSUInteger idx, BOOL *stop) {
            id obj = [remoteModel valueForKey:key];
            if (obj) {
                if ([obj isKindOfClass:[NSString class]]) {
                    [coreDataModel setValue:obj forKey:key];
                }else {
                    NSData *objData = [NSKeyedArchiver archivedDataWithRootObject:obj];
                    [coreDataModel setValue:objData forKey:key];
                }
            }
            
        }];
        free(propertyList);
        return coreDataModel;
    }else return nil;
}

存贮数据的时候调用

            specialInfoDB = makeRemoteModelToCoreDataModel(specialBO, [specialObjectBO class],specialInfoDB);

在coreData的模型中添加对应的字段，只是数据类型是NSData
如图

读取数据的时候，将coredata的所有字段赋值给我们使用的模型对象
实现的方法

id makeCoreDataModelToRemoteModel(id CoreDataModel,Class remoteDataClass) {
    int i;
    unsigned int propertyCount = 0;
    objc_property_t *propertyList = class_copyPropertyList(remoteDataClass, &propertyCount);
    
    
    NSMutableArray *propertyNameList = [NSMutableArray array];
    for ( i=0; i < propertyCount; i++ ) {
        objc_property_t *thisProperty = propertyList + i;
        const char* propertyName = property_getName(*thisProperty);
        NSString *string = [NSString stringWithFormat:@"%s",propertyName];
        [propertyNameList addObject:string];
    }
    
    if (propertyNameList.count > 0) {
        id dataModal = [[remoteDataClass alloc]init];
        [propertyNameList enumerateObjectsUsingBlock:^(NSString* key, NSUInteger idx, BOOL *stop) {
            id obj = [CoreDataModel valueForKey:key];
            if ([obj isKindOfClass:[NSString class]]) {
                [dataModal setValue:obj forKey:key];
            }else {
                id objFromData = [NSKeyedUnarchiver unarchiveObjectWithData:obj];
                [dataModal setValue:objFromData forKey:key];
            }
        }];
        free(propertyList);
        return dataModal;
    }else return nil;
}

调用

        specialObjectBO* specialBO = makeCoreDataModelToRemoteModel(specialInfoDB, [specialObjectBO class]);

这两处重点用到了字典和NSData的相互转化

NSData *dictData = [NSKeyedArchiver archivedDataWithRootObject:dict];

NSDictionary *subDict = [NSKeyedUnarchiver unarchiveObjectWithData:dictData];

注意点，我们CoreData中的字段是不能直接存贮我们自定义对象类型的，所以，如果我们要存贮的字段如果是一个自定义对象类型，则要将该字段成字段类型，然后转换成Data存贮