C++嵌套switch語句
有可能有一個switch作為外switch語句序列的一部分。即使在內外switch的case的常數包含共同的值,冇有衝突將出現。
C++規定,至少允許256層嵌套switch語句。
語法
嵌套switch語句的語法如下:
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': // ... }
例子:
#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; }
這將產生以下結果:
This is part of outer switch This is part of inner switch Exact value of a is : 100 Exact value of b is : 200