Javascript add leading zeroes to date

I've created this script to calculate the date for 10 days in advance in the format of dd/mm/yyyy:

var MyDate = new Date();
var MyDateString = new Date();
MyDate.setDate(MyDate.getDate()+10);
MyDateString = MyDate.getDate() + '/' + (MyDate.getMonth()+1) + '/' + MyDate.getFullYear();

I need to have the date appear with leading zeroes on the day and month component by way of adding these rules to the script. I can't seem to get it to work.

if (MyDate.getMonth < 10)getMonth = '0' + getMonth;

and

if (MyDate.getDate <10)get.Date = '0' + getDate;

If someone could show me where to insert these into the script I would be really appreciative.

---

Try this: http://jsfiddle.net/xA5B7/

var MyDate = new Date();
var MyDateString;

MyDate.setDate(MyDate.getDate() + 20);

MyDateString = ('0' + MyDate.getDate()).slice(-2) + '/'
             + ('0' + (MyDate.getMonth()+1)).slice(-2) + '/'
             + MyDate.getFullYear();

---

EDIT:

To explain, .slice(-2) gives us the last two characters of the string.

So no matter what, we can add "0" to the day or month, and just ask for the last two since those are always the two we want.

So if the MyDate.getMonth() returns 9 , it will be:

("0" + "9") // Giving us "09"

so adding .slice(-2) on that gives us the last two characters which is:

("0" + "9").slice(-2)
"09"

But if MyDate.getMonth() returns 10 , it will be:

("0" + "10") // Giving us "010"

so adding .slice(-2) gives us the last two characters, or:

("0" + "10").slice(-2)
"10"

---

Here is an example from the Date object docs on the Mozilla Developer Network using a custom "pad" function, without having to extend Javascript's Number prototype. The handy function they give as an example is

function pad(n){return n<10 ? '0'+n : n}

And below is it being used in context.

/* use a function for the exact format desired... */
function ISODateString(d){
    function pad(n){return n<10 ? '0'+n : n}
    return d.getUTCFullYear()+'-'
    + pad(d.getUTCMonth()+1)+'-'
    + pad(d.getUTCDate())+'T'
    + pad(d.getUTCHours())+':'
    + pad(d.getUTCMinutes())+':'
    + pad(d.getUTCSeconds())+'Z'
}

var d = new Date();
console.log(ISODateString(d)); // prints something like 2009-09-28T19:03:12Z

---

你可以定义一个“str_pad”函数（如在php中）：

function str_pad(n) {
    return String("00" + n).slice(-2);
}

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