巢狀結構
Prerequisites:
巢狀結構指的是結構中還有結構。
定義巢狀結構
結構中的結構要先定義。
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struct Address{
int zip;
char addr[100];
};
struct Student{
//學生姓名
char* name;
//學號
int id;
Address address;
};
初始化巢狀結構
初始化方式有2種。
方式一
巢狀結構的值放進大括號中。
結構 變數名 = {值1,值2,巢狀值1,巢狀值2};
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Student student = {"Mary", 1,338, "桃園市xxx"};
方式二
大括號中有大括號包著巢狀結構。
結構 變數名 = {值1,值2,{巢狀值1,巢狀值2}};
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Student student = {"Mary", 1,{338, "桃園市xxx"}};
修改巢狀結構
方式有二種。
大括號
變數名 = {值1,值2,巢狀值1,巢狀值2};
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student = {"Bill", 2, 100, "台北市xxx"};
點運算子
結構變數.巢狀結構成員 = {巢狀值1,巢狀值2};
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student.name = "Jeff";
student.id = 3;
student.address = {300,"新竹縣xxxx"};
單獨修改巢狀結構中的成員
若巢狀結構中的成員是字串，修改方式如下
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strcpy(student.address.addr, "新竹縣xxxx");
完整程式碼
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#include <iostream>
using namespace std;
struct Address{
int zip;
char addr[100];
};
struct Student{
//學生姓名
char* name;
//學號
int id;
Address address;
};
int main() {
Student student = {"Mary", 1, {338, "桃園市xxx"}};
student.name = "Jeff";
student.id = 3;
student.address.zip = 300;
strcpy(student.address.addr, "新竹縣xxxx");
cout << "After:" << endl;
cout << student.name << endl;
cout << student.id << endl;
cout << student.address.zip << endl;
cout << student.address.addr << endl;
return 0;
}
After:
Jeff
3
300
新竹縣xxxx
讀取巢狀結構成員
結構變數.巢狀結構成員.成員
student.address.zip
完整程式碼
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#include <iostream>
using namespace std;
struct Address{
int zip;
char addr[100];
};
struct Student{
//學生姓名
char* name;
//學號
int id;
Address address;
};
int main() {
Student student = {"Mary", 1, {338, "桃園市xxx"}};
cout << "Before:" << endl;
student = {"Bill", 2, 100, "台北市xxx"};
cout << student.name << endl;
cout << student.id << endl;
cout << student.address.zip << endl;
cout << student.address.addr << endl;
student.name = "Jeff";
student.id = 3;
student.address = {300,"新竹縣xxxx"};
cout << "After:" << endl;
cout << student.name << endl;
cout << student.id << endl;
cout << student.address.zip << endl;
cout << student.address.addr << endl;
return 0;
}
Before:
Bill
2
100
台北市xxx
After:
Jeff
3
300
新竹縣xxxx