极客教程C++ 嵌套开关语句
可以将开关作为外部开关语句序列的一部分。即使内部和外部开关的case常量包含相同的值，也不会出现冲突。
C++规定开关语句的嵌套层数至少允许为256级。
语法
嵌套开关语句的语法如下所示：
switch(ch1) {
case 'A':
cout << "This A is part of outer switch";
switch(ch2) {
case 'A':
cout << "This A is part of inner switch";
break;
case 'B': // ...
}
break;
case 'B': // ...
}C++
示例
#include <iostream>
using namespace std;
int main () {
// local variable declaration:
int a = 100;
int b = 200;
switch(a) {
case 100:
cout << "This is part of outer switch" << endl;
switch(b) {
case 200:
cout << "This is part of inner switch" << endl;
}
}
cout << "Exact value of a is : " << a << endl;
cout << "Exact value of b is : " << b << endl;
return 0;
}C++
这将产生以下结果−
This is part of outer switch
This is part of inner switch
Exact value of a is : 100
Exact value of b is : 200C++