C#

Question 1

What framework does C# run on?

Answer 1

The .NET Framework.

Question 2

What method is used to print to console?

Answer 2

Console.WriteLine(“message”);

Question 3

How do you use writeline placeholders?

Answer 3

Console.WriteLine(“My name is {0} and I am {1} years old”, x, y);

Question 4

What method is used to get user input?

Answer 4

Console.ReadLine();

Question 5

How do you convert value types?

Answer 5

Convert.ToXXX

int32, bool, int64

Question 6

How do you implicitely type a variable?

Answer 6

var (instead of int or bool or whatever)

Question 7

What is the difference between ++i and i++?

Answer 7

++i increments then proceeds with the expression, i++ does the opposite.

Question 8

How do you use switch cases?

Answer 8

switch (num){
case 1:
//code
break;
case 2:
//code
break;
default:
//code
}

Question 9

What does the continue keyword do?

Answer 9

Breaks the current iteration only

Question 10

How do you use conditional operator?

Answer 10

msg = Exp1 ? Exp2 : Exp 3;

Question 11

How do you set a default value for a method parameter?

Answer 11

void method(int x, int y=2);

Question 12

How can you place your arguments in any order when calling a method?

Answer 12

By calling the parameter variables in the arguments

Ex: method(x: 5, y: 8);

Question 13

How can you use references in methods and change variable values from a method?

Answer 13

with the ref keyword
void method(ref int y);
method(ref x)

Question 14

What is similar to a ref, but does not require you to initialize a variable?

Answer 14

out

Question 15

What is overloading?

Answer 15

Defining methods with the same names but with different parameters.

Question 16

What is the protected access modifier limited to?

Answer 16

Classes and descendants

Question 17

How do you use properties?

Answer 17

public string Name {get;set;} //default
public int Age {get{return age;}set{if(value­ == 0
age = 0}}

Question 18

How do you use arrays?

Answer 18

int[] myArray = new int[5];

string[] names = new string[3] {“john”, “bob”, “chloe”};

Question 19

What is a static member?

Answer 19

A member that only belongs to a class, not an object.

Question 20

What does “this” refer to?

Answer 20

The current instance of the class

Question 21

What does the readonly keyword do?

Answer 21

Makes it so a member can only be modified through a constructor.

Question 22

What is operator overloading?

Answer 22

A way of redefining operators

b + b2 (the + now works with objects)

Question 23

How do you use inheritance?

Answer 23

class Dog : Animal {}

Question 24

What is polymorphism?

Answer 24

A way to re-implement the same method name through a derived class

Question 25

How do you use polymorphism?

Answer 25

base class must have "virtual" keyword
derived class must have "override" keyword

Question 26

What are abstract classes?

Answer 26

A class that can’t be instantiated.

Question 27

What is the advantage of using an interface?

Answer 27

A class can implement multiple interfaces

Question 28

How do you use exceptions?

Answer 28

try{
//code
}
catch(Exception e){
//code
}
finally{}

Question 29

How do you use generics?

Answer 29

void method­(T a, T b){
//code
}
method(a, b); //could have been , , etc.