话不多说 看代码

#import <Foundation/Foundation.h>
@protocol NSObjectDelegate <NSObject>
// 提供一个协议，只要准备这个协议的类，都能把数组中的字典转模型
+ (NSDictionary *)arrayContainModelClass;
@end
@interface NSObject (Category)
+ (instancetype)initWithDict:(NSDictionary *)dict;
@end


//  NSObject+Category.m
//  RunTimeTest
//  Created by tuhaisheng on 17/3/7.
//  Copyright © 2017年 tuhaisheng. All rights reserved.
#import "NSObject+Category.h"
#import "objc/runtime.h"
@implementation NSObject (Category)
+ (instancetype)initWithDict:(NSDictionary *)dict{
    id objc = [[self alloc] init];
    unsigned int count;
    //获取类中的所有成员属性
    Ivar * ivarList = class_copyIvarList(self, &count);
    for (int i = 0; i < count; i++) {
        Ivar ivar = ivarList[i];
    //获取成员属性名
        NSString * name = [NSString stringWithUTF8String:ivar_getName(ivar)];
        NSLog(@"===name===%@=====",name);
        NSString * key = [name substringFromIndex:1];
        id value = dict[key];
        //value 是否是字典
        if ([value isKindOfClass:[NSDictionary class]]) {
            //获取成员属性类型
            NSString * type = [NSString stringWithUTF8String:ivar_getTypeEncoding(ivar)];
            NSRange range = [type rangeOfString:@"\""];
            type = [type substringFromIndex:range.location + range.length];
            range = [type rangeOfString:@"\""];
            // 裁剪到哪个角标，不包括当前角标
            type = [type substringToIndex:range.location];
            
            // 根据字符串类名生成类对象
            Class modelClass = NSClassFromString(type);
            if (modelClass) {
                value = [modelClass initWithDict:value];
            }
        }
        
        if ([value isKindOfClass:[NSArray class]]) {
            if ([self respondsToSelector:@selector(arrayContainModelClass)]) {
                //
                id idSelf = self;
                NSString *type = [idSelf arrayContainModelClass][key];
                // 生成模型
                Class classModel = NSClassFromString(type);
                NSMutableArray *arrM = [NSMutableArray array];
                // 遍历字典数组，生成模型数组
                for (NSDictionary *dict in value) {
                    // 字典转模型
                    id model =  [classModel initWithDict:dict];
                    [arrM addObject:model];
                }
                // 把模型数组赋值给value
                value = arrM;
            }
        }
        if (value) { // 有值，才需要给模型的属性赋值
            // 利用KVC给模型中的属性赋值
            [objc setValue:value forKey:key];
        }
    }
    return objc;
}
@end
不管是字典里面包含数组还是字典，都会以 [objc setValue:value forKey:key];来执行。
arrayContainModelClass 这个是一个协议，只要准备这个协议的类，都能把数组中的字典转模型
+ (NSDictionary *)arrayContainModelClass{
    return @{@"person":@"Person"};
}