IOS开发之路--C语言构造类型

//
// main.c
// ConstructedType
//
// Created by Kenshin Cui on 14-7-18.
// Copyright (c) 2014年 Kenshin Cui. All rights reserved.
//

#include <stdio.h>

//结构体类型Date
struct Date{
 int year;
 int month;
 int day;
};

struct Person{
 char *name;
 int age;
 struct Date birthday;//一个结构体中使用了另一个结构体类型，结构体类型变量声明前必须加上struct关键字
 float height;
};

int main(int argc, const char * argv[]) {
 struct Person p={"Kenshin",28,{1986,8,8},1.72};
 //定义结构体变量并初始化,不允许先定义再初始化，例如：struct Person p;p={"Kenshin",28,{1986,8,8},1.72};是错误的
 
 printf("name=%s,age=%d,birthday=%d-%d-%d,height=%.2f\n",p.name,p.age,p.birthday.year,p.birthday.month,p.birthday.day,p.height); 
 //结果：name=Kenshin,age=28,birthday=1986-8-8,height=1.72，结构体的引用是通过"结构体变量.成员名称"
 
 printf("len(Date)=%lu,len(Person)=%lu\n",sizeof(struct Date),sizeof(struct Person)); 
 //结果：len(Date)=12,len(Person)=32
 
 return 0;
}

//
// main.c
// ConstructedType
//
// Created by Kenshin Cui on 14-7-18.
// Copyright (c) 2014年 Kenshin Cui. All rights reserved.
//

#include <stdio.h>

struct Date{
 int year;
 int month;
 int day;
};

struct Person{
 char *name;
 int age;
 struct Date birthday;
 float height;
};

void changeValue(struct Person person){
 person.height=1.80;
}

int main(int argc, const char * argv[]) {
 struct Person persons[]={
  {"Kenshin",28,{1986,8,8},1.72},
  {"Kaoru",27,{1987,8,8},1.60},
  {"Rosa",29,{1985,8,8},1.60}
 };
 for (int i=0; i<3; ++i) {
  printf("name=%s,age=%d,birthday=%d-%d-%d,height=%.2f\n",
    persons[i].name,
    persons[i].age,
    persons[i].birthday.year,
    persons[i].birthday.month,
    persons[i].birthday.day,
    persons[i].height);
 }
 /*输出结果：
  name=Kenshin,age=28,birthday=1986-8-8,height=1.72
  name=Kaoru,age=27,birthday=1987-8-8,height=1.60
  name=Rosa,age=29,birthday=1985-8-8,height=1.60
  */
 
 
 
 struct Person person=persons[0];
 changeValue(person);
 printf("name=%s,age=%d,birthday=%d-%d-%d,height=%.2f\n",
   persons[0].name,
   persons[0].age,
   persons[0].birthday.year,
   persons[0].birthday.month,
   persons[0].birthday.day,
   persons[0].height);
 /*输出结果：
  name=Kenshin,age=28,birthday=1986-8-8,height=1.72
  */
 
 
 struct Person *p=&person;
 printf("name=%s,age=%d,birthday=%d-%d-%d,height=%.2f\n",
   (*p).name,
   (*p).age,
   (*p).birthday.year,
   (*p).birthday.month,
   (*p).birthday.day,
   (*p).height);
 /*输出结果：
  name=Kenshin,age=28,birthday=1986-8-8,height=1.72
  */
 printf("name=%s,age=%d,birthday=%d-%d-%d,height=%.2f\n",
   p->name,
   p->age,
   p->birthday.year,
   p->birthday.month,
   p->birthday.day,
   p->height);
 /*输出结果：
  name=Kenshin,age=28,birthday=1986-8-8,height=1.72
  */
 
 return 0;
}

//
// main.c
// ConstructedType
//
// Created by Kenshin Cui on 14-7-18.
// Copyright (c) 2014年 Kenshin Cui. All rights reserved.
//

#include <stdio.h>

enum Season{ //默认情况下spring=0，summer=1,autumn=2,winter=3
 spring,
 summer,
 autumn,
 winter
};

int main(int argc, const char * argv[]) {
 enum Season season=summer; //枚举赋值,等价于season=1
 printf("summer=%d\n",season); //结果：summer=1
 
 for(season=spring;season<=winter;++season){
  printf("element value=%d\n",season);
 }
 /*结果：
  element value=0
  element value=1
  element value=2
  element value=3
  */
 return 0;
}

//
// main.c
// ConstructedType
//
// Created by Kenshin Cui on 14-7-20.
// Copyright (c) 2014年 Kenshin Cui. All rights reserved.
//

#include <stdio.h>

union Type{
 char a;
 short int b;
 int c;
};

int main(int argc, const char * argv[]) {
 union Type t;
 t.a='a';
 t.b=10;
 t.c=65796;
 
 printf("address(Type)=%x,address(t.a)=%x,address(t.b)=%x,address(t.c)=%x\n",&t,&t.a,&t.b,&t.c);
 //结果：address(Type)=5fbff7b8,address(t.a)=5fbff7b8,address(t.b)=5fbff7b8,address(t.c)=5fbff7b8
 
 printf("len(Type)=%d\n",sizeof(union Type));
 //结果：len(Type)=4
 
 printf("t.a=%d,t.b=%d,t.c=%d\n",t.a,t.b,t.c);
 //结果:t.a=4,t.b=260,t.c=65796
 
 return 0;
}