#import <UIKit/UIKit.h>

NS_ASSUME_NONNULL_BEGIN

@interface SecondViewController : UIViewController
@property (nonatomic,copy)NSString * name;
@end

NS_ASSUME_NONNULL_END

#import "SecondViewController.h"
#import <objc/runtime.h>
@interface SecondViewController ()
@property (nonatomic,strong)NSMutableDictionary * backingStore;
@end

@implementation SecondViewController
@dynamic name;
- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
}
-(instancetype)init{
    if (self = [super init]) {
        _backingStore = [NSMutableDictionary new];
    }
    return self;
}
+(BOOL)resolveInstanceMethod:(SEL)sel{
    NSString * selectorString = NSStringFromSelector(sel);
    if ([selectorString containsString:@"set"]) {
        class_addMethod(self, sel, (IMP)autoDictionarySetter, "v@:@");
    }else{
        class_addMethod(self, sel, (IMP)autoDictionaryGetter, "@@:");
    }
    return YES;
}
void autoDictionarySetter(id self ,SEL _cmd, id value){
    SecondViewController * typeSelf = (SecondViewController *)self;
   NSMutableDictionary * backingStore =  typeSelf.backingStore ;
    NSString * selectorString = NSStringFromSelector(_cmd);
    NSMutableString * key = [selectorString mutableCopy];
    [key deleteCharactersInRange:NSMakeRange(key.length-1, 1)];
    [key deleteCharactersInRange:NSMakeRange(0, 3)];
    NSString * lowerCaseFirstChar = [[key substringToIndex:1] lowercaseString];
    [key replaceCharactersInRange:NSMakeRange(0, 1) withString:lowerCaseFirstChar];
    if (value) {
        [backingStore setObject:value forKey:key];
    }else{
        [backingStore removeObjectForKey:key];
    }
    
    
}


id autoDictionaryGetter (id self , SEL _cmd){
    SecondViewController * typeSelf = (SecondViewController *)self;
    NSMutableDictionary * backingStor = typeSelf.backingStore;
    NSString * key = NSStringFromSelector(_cmd);
    return [backingStor objectForKey:key];
}
@end

使用访问器方法

  SecondViewController * vc = [[SecondViewController alloc]init];
    vc.name = @"123";
    NSLog(@"%@",vc.name);

这个就是使用动态方法解析，往类中添加新的方法的实践。