Javascript 将 foreach 转换为模循环

Question

Noob question here. I am trying to convert this forEach to a For loop but for some reason, this is returning undefined:

This is the forEach:

This is the for Loop that keeps displaying undefined:

Feel like such a nob for asking this but

Answer 1

Change the condition in your if statement from number%3==0 to number[i]%3==0 . Currently, you are checking if the whole list (number) is divisible by 3 or not. By changing, the condition you check if the particular iteration's index is divisible by 3 or not, also change i=1 to i=0 , this wail start your loop from the first index.

Answer 2

In your if condition, you are having condition number % 3 instead of number[i] % 3 Correct code:

 var number = [1,2,3,4,5,6,7,8,9]; for(var i=0; i<number.length;i++){ if(number[i]%3 == 0){ alert(number[i]); } }