[thelist] [JS] isDate function

Joshua Olson joshua at waetech.com
Tue Mar 8 11:49:49 CST 2005

Hi list,

After searching the web for isDate functions I found myself unhappy with
most of them.  Too long, too tedious, etc.  So, I made my own to parse
normal US formatted dates (MM/DD/YYYY).  Can anybody spot a reason why the
following code wouldn't work?

function removeLeadingZeros(str)
  while (str.charAt(0) == '0')
    str = str.substr(1);
  return str;

function isDate(str)
    arr = str.split('/');
    month = parseInt(removeLeadingZeros(arr[0])) - 1;
    day = parseInt(removeLeadingZeros(arr[1]));
    year = parseInt(removeLeadingZeros(arr[2]));
    var d = new Date(year, month, day);
    return d.getMonth() == month && d.getFullYear() == year && d.getDate()
== day;
    return false;

Basic premise... split the string at the brackets.. create a date object
based on the values, then compare the date object's components against the
original values.  If they match, everything was OK.  If not, fail.

Joshua Olson
Web Application Engineer
WAE Tech Inc.

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