Adding extra zeros in front of a number using jQuery?

Question

I have file that are uploaded which are formatted like so

MR 1

MR 2

MR 100

MR 200

MR 300

Answer 1

In simple terms we can written as follows,

for(var i=1;i<=31;i++)
    i=(i<10) ? '0'+i : i;

//Because most of the time we need this for day, month or amount matters.