[JavaScript] 시간숫자 HH:MM 포멧팅

//시간 시간:분분 format 만들기
function _fnFormatTime(vTime)
{
    if (String(vTime).length > 3) {
        return String(vTime).replace(/(\d{2})(\d{2})/, '$1:$2');
    }
    else {
        var vValue = "0" + String(vTime)
        return vValue.replace(/(\d{2})(\d{2})/, '$1:$2');
    }
}