//
//  Person.h#import <Foundation/Foundation.h>@interface Person : NSObject@property int age;
@property NSString *name;/*自定义构造方法:其实就是自定义一个init方法1.一定是对象方法2.一定返回id/instancetype3.方法名称一定以init开头
*/
- (instancetype)initHwwAge:(int)age;// 一个类可以有0个或者多个自定义构造方法
- (instancetype)initWithName:(NSString *)name;// 自定义构造方法可以有1个或多个参数
- (instancetype)initWithAge:(int)age andName:(NSString *)name;
@end

//
//  Person.m#import "Person.h"@implementation Person- (instancetype)init
{if (self = [super init]) {_age = 10;}return self;
}- (NSString *)description
{return [NSString stringWithFormat:@"age = %i, name = %@", _age, _name];
}- (instancetype)initHwwAge:(int)age
{if (self = [super init]) {_age = age;}return self;
}- (instancetype)initWithName:(NSString *)name
{if (self  =[super init]) {_name = name;}return self;
}- (instancetype)initWithAge:(int)age andName:(NSString *)name
{if (self = [super init]) {_age = age;_name = name;}return self;
}
@end

//
//  main.m
//  自定义构造方法#import <Foundation/Foundation.h>
#import "Person.h"int main(int argc, const char * argv[]) {Person *p9 = [Person new];//_age=10,_name=nilPerson *p8 = [[Person alloc] init];p8.age = 20;//_age=10,_name=nilPerson *p7 = [[Person alloc] initHwwAge:20];//_age=20,_name=nilPerson *p6 = [[Person alloc] initWithName:@"lnj"];//_age=0,_name=@"lnj"Person *p5 = [[Person alloc] initWithAge:20 andName:@"lnj"];//_age=20,_name=@"lnj"NSLog(@"%@", p5);Person *p4 = [[Person alloc] init];p4.age = 30;//_age=30,_name=nilPerson *p3 = [[Person alloc] initHwwAge:30];//_age=30,_name=nilPerson *p23 = [[Person alloc] initWithName:@"lmj"];//_age=0,_name=@"lmj"Person *p2 = [[Person alloc] initWithAge:30 andName:@"lmj"];//_age=30,_name=@"lmj"NSLog(@"%@", p2);return 0;
}