Here is the syntax of using C# if else statement in a single line.
  1. (Condition) ? "Value For true":" Value For False "
OK, here is your typical if else statement:
  1. if(x==1)
  2. {
  3. x=10;
  4. }
  5. else
  6. {
  7. x=15;
  8. }
This is how we can replace the above code block in a single line:
  1. x=(x==1)?10:15;
Here is a detailed tutorial, How To Use C# If Else Statement