C# Questions & Answers on Switch Statements for Freshers

1. Select the output for the following set of code.

1.   static void Main(string[] args)

2.   {

3.       int movie = 1;

4.       switch (movie << 2 + movie)

5.       {

6.       default: 

7.           Console.WriteLine("3 Idiots");

8.           break;

9.       case 4: 

10.           Console.WriteLine("Ghazini");

11.           break;

12.       case 5: 

13.           Console.WriteLine("Krishh");

14.           break;

15.       case 8: 

16.           Console.WriteLine("Race");

17.           break;

18.       }

19.       Console.ReadLine();

20.   }

a) 3 Idiots
b) Ghazini
c) Race
d) Krishh

Answer: c

Explanation: We can put ‘default’ case in any order and hence write cases in any order.
Output: Race.

2. Select the output for the following set of code :

1.   static void Main(string[] args)

2.   {

3.       int i = 2, j = 4;

4.       switch (i + j * 2)

5.       {

6.       case 1 :

7.       case 2 :

8.           Console.WriteLine("1 and 2");

9.           break;

10.       case 3 to 10:

11.           Console.WriteLine("3 to 10");

12.           break;

13.       }

14.       Console.ReadLine();

15.   }

a) 3 to 10 will be printed
b) 1 and 2 will be printed
c) The code reports an error as missing ; before :
d) The code gives output as 3 to 10

Answer: c

Explanation: Syntax error- switch case does not work with syntax as 3 to 10:
Output :
static void Main(string[] args)
{
int i = 2,j = 4;
switch (i + j * 2)
{
case 1 :
case 2 :
Console.WriteLine(“1 and 2”);
break;
case 3 :
Console.WriteLine(“3 to 10”);
break;
}
Console.ReadLine();
}
Here i = 2,j = 4.So,(i + j * 2) gives output as 10 and case 10 is missing.So,prints nothing for given code.

3. Select the output for the following set of code :

1.  static void Main(string[] args)

2.  {

3.      int i = 2, k = 3;

4.      switch (i - k)

5.      {

6.      case -1:

7.          ++i;

8.          ++k;

9.          break;

10.      case 2:

11.          --i;

12.          ++k;

13.          break;

14.      default:

15.          i += 3;

16.          k += i;

17.          break;

18.      }

19.      Console.WriteLine(i + "\n" + k);

20.      Console.ReadLine();

21.  }

a) 2 3 3
b) 3 2 3
c) 3 4 4
d) 5 10 10

Answer: c

Output: 3
4
4
Explanation: i – k = -1.So, case -1 will be executed only.

4. Select output for the following set of code :

1.    static void Main(string[] args)

2.    {

3.        int const p = 0;

4.        switch (3 * 5 / 6)

5.        {

6.        case p: 

7.            Console.WriteLine("A");

8.            break;

9.        case p * 1:

10.            Console.WriteLine("B");

11.            break;

12.        case p - 2:

13.            Console.WriteLine("C");

14.            break;

15.        default: 

16.            Console.WriteLine("D");

17.        }

18.   }

a) A
b) B
c) C
d) Compile time error

Answer: d

Explanation: In case expression we don’t have constant variable.

5. Select output for the following set of code :

1.  static void Main(string[] args)

2.  {

3.      int i = 2, j = 3, k = 4;

4.      switch (i + j - k)

5.      {

6.      case 0: case 2: case 4:

7.          ++i;

8.          k += j;

9.          break;

10.      case 1: case 3: case 5 :

11.          --i;

12.          k -= j;

13.          break;

14.      default:

15.          i += j;

16.          break;

17.      }

18.      Console.WriteLine(i + "\n" + j + "\n" + k);

19.      Console.ReadLine();

20.  }

a) 1 3 1
b) 2 3 4
c) 5 3 4
d) Compile time error.

Answer: a

Explanation: Solving expression (i + j – k) gives 1 and hence,solving for case 1:case 3:case 5:.
Output : 1
3
1

6. Select the output for the following set of code :

1.   static void Main(string[] args)

2.   {

3.       int  i = 9 , j = 7;

4.       switch (i - j + 3)

5.       {

6.       case 9: 7:

7.           j += 6;

8.           break;

9.       case 5:

10.           i -= 4;

11.           break;

12.       }

13.       Console.WriteLine(i + "\n" + j);

14.       Console.ReadLine();

15.   }

a) 5 7
b) 9 13
c) Compile time error
d) 9 7

Answer: c

Explanation: Invalid expression’7:’ in case 9:7:.

7. Select the output for the following code :

1.   static void Main(string[] args)

2.   {

3.       switch (5)

4.       {

5.       case 5.0f: 

6.           Console.WriteLine("harsh");

7.           break;

8.       case 5: 

9.           Console.WriteLine("amish");

10.           break;

11.       case 5.0L: 

12.           Console.WriteLine("ANKIT");

13.           break;

14.       default:

15.           Console.WriteLine("ashish");

16.       }

17.       Console.ReadLine();

18.    }

a) amish
b) ANKIT
c) harsh
d) Compile time error

Answer: d

Explanation: Only integral values are allowed for case expression.
5.0f = (int)5.0f.
5.0L =(int)5.0L.

8. Select output for the following code:

1.   static void Main(string[] args)

2.   {

3.       int i;

4.       int j = 1;

5.       int []ar = {21, 22, 13, 4};

6.       switch (ar[j])

7.       {

8.       case 1:

9.           i++;

10.           break;

11.       case 2:

12.           i += 2;

13.           j = 3;

14.           continue;

15.       case 3: 

16.          i %= 2;

17.          j = 4;

18.          continue;

19.       default: 

20.          --i;

21.       }

22.       Console.WriteLine(i);

23.       Console.ReadLine();

24.   }

a) 23
b) 15
c) Compile time error
d) 12

Answer: c

Explanation: Continue cannot be used as a part of switch statement.
Output :
static void Main(string[] args)
{
int i;
int j = 1;
int []ar = {21 , 22, 13, };
switch(ar[j])
{
case 1:
i++;
break;
case 2:
i += 2;
j = 3;
continue;
case 3:
i %= 2;
j = 4;
default:
–i;
}
Console.WriteLine(i);
Console.ReadLine();
}

9. Select the output for the following set of Code:

1.  static void Main(string[] args)

2.  {

3.      char ch = Convert.ToChar('a' | 'b' | 'c');

4.      switch (ch)

5.      {

6.      case 'A':

7.      case 'a':

8.          Console.WriteLine("case A|case a");

9.          break;

10.      case 'B':

11.      case 'b':

12.          Console.WriteLine("case B|case b");

13.          break;

14.      case 'C':

15.      case 'c':

16.      case 'D':

17.      case 'd':

18.          Console.WriteLine("case D|case d");

19.          break;

20.      }

21.      Console.ReadLine();

22.  }

a) Compile time error
b) case A|case a
c) case B|case b
d) case D|case d

Answer: d

Explanation: Case statement declared last will only be executed as no particular casenumber is declared is to be called.
Output : case D|case d

10. Select the output for the following set of Code:

1.   static void Main(string[] args)

2.   {

3.       char ch = 'p';

4.       switch (ch)

5.       {

6.       case 'p':

7.           Console.WriteLine("coco" + "\t" + Convert.ToInt32(ch));

8.           break;

9.       default:

10.           Console.WriteLine("default");

11.           break; 

12.      }

13.      Console.WriteLine("main");

14.   }

a) coco main
b) coco 112
c) coco 112 main
d) compile time error

Answer: c

Explanation: ASCII value of ‘p’ is 112.Hence, coco 112 main.
Output: coco 112 main.