可能一個switch作為另一個switch語句序列的一部分。即使在內外switch的case語句的常數包含共同的值，但是不會有衝突將出現。

語法

嵌套switch語句的語法如下：

switch(ch1) {
   case 'A': 
      printf("This A is part of outer switch" );
      switch(ch2) {
         case 'A':
            printf("This A is part of inner switch" );
            break;
         case 'B': /* case code */
      }
      break;
   case 'B': /* case code */
}

例子：

#include <stdio.h>
 
int main ()
{
   /* local variable definition */
   int a = 100;
   int b = 200;
 
   switch(a) {
      case 100: 
         printf("This is part of outer switch
", a );
         switch(b) {
            case 200:
               printf("This is part of inner switch
", a );
         }
   }
   printf("Exact value of a is : %d
", a );
   printf("Exact value of b is : %d
", b );
 
   return 0;
}

讓我們編譯和運行上麵的程序，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