How do I check for vowels in JavaScript?

Question

I\'m supposed to write a function that takes a character (i.e. a string of length 1) and returns true if it is a vowel, false otherwise. I came up with two functions, but do

Answer 1

function isVowel(char)
{
  if (char.length == 1)
  {
    var vowels = "aeiou";
    var isVowel = vowels.indexOf(char) >= 0 ? true : false;

    return isVowel;
  }
}

Basically it checks for the index of the character in the string of vowels. If it is a consonant, and not in the string, indexOf will return -1.