<script>
    function getVowels(string) {
        var Vowels = 'aAeEiIoOuU';
        var vowelsCount = 0;
        for(var i = 0; i < string.length ; i++) {
            if (Vowels.indexOf(string[i]) !== -1) {
                vowelsCount += 1;
            }
        }
        return vowelsCount;
    }
    console.log("The Number of vowels in -"+
    " A Computer Science Portal for Geeks:" 
    + getVowels("A Computer Science Portal for Geeks"));
</script>

The Number of vowels in - A Computer Science Portal for Geeks:12