ios 获取与修改类私有属性与实例变量
1 #import "Cat.h" 2 3 @interface Cat () 4 5 @property (nonatomic, copy) NSString *name; 6 7 @end 8 9 @implementation Cat{ 10 int age; 11 } 12 13 -(instancetype)initWithName:(NSString *)string{ 14 self = [super init]; 15 if (self) { 16 _name = string; 17 age = 1; 18 } 19 return self; 20 } 21 22 @end
Cat *cat = [[Cat alloc]initWithName:@"大懒猫"]; NSLog(@"第一种,通过kvc获取与修改属性以及实例变量age\n\n"); //第一种,通过kvc获取与修改属性以及实例变量age NSString *cat_name = [cat valueForKey:@"name"]; [cat setValue:@"大花猫" forKey:@"name"]; NSString *cat_name_modified = [cat valueForKey:@"_name"];//key值为name与_name都可以,因为程序运行时会去类中找,先找同名的,再找带有下划线_的,找不到就报错。 NSLog(@"name修改前:%@, 修改后:%@",cat_name,cat_name_modified); //打印结果:name修改前:大懒猫, 修改后:大花猫 int age = [[cat valueForKey:@"age"]intValue]; [cat setValue:@2 forKey:@"age"]; int age_mod = [[cat valueForKey:@"age"]intValue]; NSLog(@"age修改前:%d, 修改后:%d",age,age_mod); //打印结果:age修改前:1, 修改后:2 NSLog(@"\n\n第二种,通过runtime获取与修改属性\n\n"); //第二种,通过runtime获取与修改属性 Ivar m_name = class_getInstanceVariable([Cat class], "_name"); cat_name = (NSString *)object_getIvar(cat, m_name); NSLog(@"name修改前:%@",cat_name); //打印结果:name修改前:大花猫 object_setIvar(cat, m_name, @"大脸猫"); cat_name = (NSString *)object_getIvar(cat, m_name); NSLog(@"name修改:%@",cat_name); //打印结果:name修改:大脸猫