學點 C 語言(24): 資料類型 – 結構(struct)

1. 結構就是多個變數的集合:

#include <stdio.h>int main(void){    struct Rec {        int x;        int y;    };    struct Rec r1;    r1.x = 111;    r1.y = 222;    printf("%d, %d", r1.x, r1.y);        getchar();    return 0;}

2. 定義時同時聲明變數:

#include <stdio.h>int main(void){    struct Rec {        int x,y;    } r1,r2;    r1.x = 111;    r1.y = 222;    r2.x = 333;    r2.y = 444;    printf("%d, %d\n", r1.x, r1.y);    printf("%d, %d\n", r2.x, r2.y);        getchar();    return 0;}

3. 定義時同時聲明變數並賦值:

#include <stdio.h>int main(void){    struct Rec {        int x,y;    } r1 = {777,888};    printf("%d, %d\n", r1.x, r1.y);        getchar();    return 0;}

#include <stdio.h>int main(void){    struct Rec {        char  name[12];        short age;    } r1 = {"ZhangSan", 12};    printf("%s, %u", r1.name, r1.age);        getchar();    return 0;}

4. 聲明變數是賦初值:

#include <stdio.h>int main(void){    struct Rec {        char  name[12];        short age;    };    struct Rec r1 = {"ZhangSan", 12};    printf("%s, %u", r1.name, r1.age);        getchar();    return 0;}

5. 聲明後給字串賦值有點麻煩:

#include <stdio.h>#include <string.h>int main(void){    struct Rec {        char  name[12];        short age;    };    struct Rec r1;    strcpy(r1.name, "ZhangSan");    r1.age  = 18;    printf("%s, %u", r1.name, r1.age);        getchar();    return 0;}

6. 如果在定義時直接聲明變數, 可省略結構名:

#include <stdio.h>int main(void){    struct {        char  name[12];        short age;    } r1 = {"ZhangSan", 12};    printf("%s, %u", r1.name, r1.age);        getchar();    return 0;}

7. 通過 scanf 賦值:

#include <stdio.h>int main(void){    struct Rec {        char  name[12];        short age;    } r1;    printf("name: ");    scanf("%s", r1.name);    printf("age: ");    scanf("%d", &r1.age);    printf("Name: %s; Age: %d", r1.name, r1.age);        getchar(); getchar();    return 0;}