C# Interview Questions - Part One

Named parameters provide provision for developers to pass parameters in any order.

1. Here is the sample: static void Main(string[] args) {
2. try {
3. namedParameters(secondParameters: "this is second", thirdParameters: "this is third", firstParameters: "this is first");
4. } catch (Exception e) {
5. Console.WriteLine(e.GetType());
6. throw;
7. }
8. }
9. public static void namedParameters(string firstParameters, string secondParameters, string thirdParameters) {
10. Console.WriteLine(firstParameters + "," + secondParameters + "," + thirdParameters);
11. Console.ReadLine();
12. }

When you execute the above code, you will see the below output.

“this is first, this is second,this is third”

10. What are optional parameters?

Optional parameters provide provision to mark specific arguments as optional.

Here is the sample,

1. static void Main(string[] args) {
2. try {
3. optionalParameters(secondParameters: "this is second", firstParameters: "this is first");
4. } catch (Exception e) {
5. Console.WriteLine(e.GetType());
6. throw;
7. }
8. }
9. public static void optionalParameters(string firstParameters, string secondParameters, string thirdParameters = "this is optional") {
10. Console.WriteLine(firstParameters + "," + secondParameters + "," + thirdParameters);
11. Console.ReadLine();
12. }

Output

“this is first, this is second,this is optional”

11. What is the output of the below code?
    
    1. static void Main(string[] args) {
    2. try {
    3. Console.WriteLine("Enum value for Orange is: " + (int) Colors.Orange);
    4. Console.ReadLine();
    5. } catch (Exception e) {
    6. Console.WriteLine(e.GetType());
    7. throw;
    8. }
    9. }
    10. public enum Colors {
    11. Blue = 1,
    12. Green = Blue | 2,
    13. Red = Blue | Green,
    14. Black = 4, White = 5,
    15. Orange = Red | White
    16. }

Enum value for Orange is: 7

12. What is enum?
    
    Enum is used to define a set of constants.

13. What is the purpose of Action<T> delegate?
    
    It encapsulates a method that has a single parameter and doesn’t return any value.

14. What set of statements do you use in a continue statement?
    
    while, do, for, or foreach.

15. What is the purpose of XSD?
    
    XSD is used to validate an XML document.