How the '?' And ':' Operator works in C#?

Question

i have been seeing these several times without knowing what is it. maybe i missed something in the lesson... is it an operator? still need your help!

what does it do, when do you use it best, and maybe an example if possible please...

Answer 1

Yeah, its really nice for return values. Look at this recursive factorial example:
int Factorial(int n)
{
return ((n == 1) ? 1 : n * Factorial(n - 1));
}

Answer 2

Your welcome :)

Answer 3

The : operator is used in inheritance:
public class Dog : Animal
{
public Dog() : base()
{}
}

The ? operator is used when you want to allow a variable to be able to take null as a value:
int? a = null;
double? b = null;
etc...

Both operators are also used in conditional expressions:

int x = (0 > 1) ? 4 : 5;
If the condition within the brackets is true the value of x will be 4 (the value before the : operator) else it will be 5 (the value after the : operator). In this case it will be 5

Answer 4

ooh. its like an if else but in short

Answer 5

i understand now. thank you

Answer 6

Unnecessary extra information: This operator is known as the "ternary conditional operator", or usually just the "ternary operator" since there aren't any other ternary operators (in C#, that is. This may be false, someone please correct me if I'm wrong).