// Person.h #import <Foundation/Foundation.h> @interface Person : NSObject @property int age; //属性是_age @end
// // Person.m #import "Person.h" @implementation Person - (instancetype)init { if (self = [super init]) { _age = 10; [self setAge:100]; } return self; } - (NSString *)description { return [NSString stringWithFormat:@"age = %i", _age]; } @end
// // Studnet.h #import "Person.h" @interface Studnet : Person @property int no; // 学号, 属性是_no, @end
// // Studnet.m #import "Studnet.h" @implementation Studnet - (instancetype)init { if (self = [super init]) { // [self setAge:11]; _no = 1; [self setNo:22]; } return self; } - (NSString *)description { return [NSString stringWithFormat:@"age = %i , no = %i,%i", [self age], _no,[self no]]; } @end
// // main.m // 构造方法练习 #import <Foundation/Foundation.h> #import "Person.h" #import "Studnet.h" int main(int argc, const char * argv[]) { Person *p = [[Person alloc] init]; NSLog(@"%@", p); Person *p1 = [[Person alloc] init]; NSLog(@"%@", p1); Studnet *stu = [[Studnet alloc] init]; NSLog(@"%@", stu); Studnet *stu1 = [[Studnet alloc] init]; NSLog(@"%@", stu1); return 0; }