1.繼承中的自定義構(gòu)造方法

• 不能在子類訪問(wèn)父類私有變量

@interface Person : NSObject

@property int age;

- (id)initWithAge:(int)age;
@end



@interface Student : Person

@property NSString *name;

- (id)initWithAge:(int)age andName:(NSString *)name;
@end

@implementation Student

- (id)initWithAge:(int)age andName:(NSString *)name
{
    if (self = [super init]) {
//        這個(gè)_Age是父類中通過(guò)property自動(dòng)在.m中生成的無(wú)法繼承,不能直接訪問(wèn)
//        _age = age;
        [self setAge:age];
        _name = name;
    }
    return self;
}
@end

• 父類的屬性交給父類的方法來(lái)處理

@interface Person : NSObject

@property int age;

- (id)initWithAge:(int)age;
@end



@interface Student : Person

@property NSString *name;

- (id)initWithAge:(int)age andName:(NSString *)name;
@end

@implementation Student

- (id)initWithAge:(int)age andName:(NSString *)name
{
    if (self = [super initWithAge:age]) {
        _name = name;
    }
    return self;
}
@end

initsuper.png

2.自定義構(gòu)造方法的使用注意

• (1)自己做自己的事情
• (2)父類的屬性交給父類的方法來(lái)處理,子類的方法處理子類自己獨(dú)有的屬性
• 自定義構(gòu)造方法必須以intiWith開(kāi)頭,并且’W’必須大寫(xiě)