为什么不会“||” （或）在我的 javascript function 中工作？

Question

I am trying to write the code so that if if given 2 numbers that represent my birthday (month = 11, day = 3) it would log "how did you know". anything else would return "Just Another Day". Also need the order of month and day to not matter.

I have written it as:

function birthday (month,day){
  let result;
  if( month == "11" && day == "3") || (day == "3" && month = "11"){
      result = "How did you know?";
     }
      else {
       result = "Just Another Day";
      }
  return result;
}

console.log(birthday(3, 11));

but it returns and tell me the || (or) is an unexpected token...How else could I write this?

Answer 1

You have two conditions on the two sides of the || operator that say the exact same thing. On the second condition, you need to check if the day is 11 and the month 3. Additionally, you have = operator on the last comparison instead of a == :

if ((month == "11" && day == "3") || (month == "3" && day == "11")) {

Answer 2

You should add "(" after if and add ")" after (day == "3" && month == "11") .Also change = operator on the last comparison to == and change last comparison from (day == "3" && month == "11") to (month == "3" && day == "11") . Change your code to this code:

 function birthday (month,day){ let result; if( (month == "11" && day == "3") || (month == "3" && day == "11")){ result = "How did you know?"; } else { result = "Just Another Day"; } return result; } console.log(birthday(3, 11));

Answer 3

I modify your code, the last comparison symbol (==) was wrong, it was an asignment symbol(=) and you are comparing day and month twice, now your code works fine!

 function birthday (month, day){ let result = ""; if(( month == "11" && day == "3") || (month == "3" && day == "11")){ result = "How did you know?"; } else { result = "Just Another Day"; } return result; } console.log(birthday(3, 11));