Untitled

Date validation with switch command does not work
function validateDateFormat(day,month,year) {
    alert(month); // this was to ensure month was correct and it is!!
    var maxDay = 0;
    switch(month)
    {
        case 01 :
        case 03 :
        case 05 :
        case 07 :
        case 08 :
        case 10 :
        case 12 : maxDay = 31; break;
        case 04 :
        case 06 :
        case 09 :
        case 11 : maxDay = 30; break;
        case 02 : if(year%4 == 0) maxDay = 29;
              else maxDay = 28;
              break;
        //default : return " Invalid month -"; break;
    }
    alert(maxDay);
    if(day > maxDay) {return " Invalid day -";}
    return "";
}

var num = "9";
if (num == 9)
    alert("true");

var num = "9";
switch(num) {
    case 9:
        alert("true");
        break;
}

var num = "9";
switch(num) {
    case "9": // string
        alert("true");
        break;
}