[jQuery] Re: validate plugin date()

[Dave Methvin]

> I have a date filed that needs to be validated only for  
> one type of date format: mm/dd/yyy.
> is there a way to restrict that to only one format?

This should work for validating USA-style mm/dd/yyyy dates.

$.validator.addMethod("usadate", function(value, element){
   // Start with basic match for digits and slashes
   var mdy = value.match(/(\d{1,2})\/(\d{1,2})\/(\d{4})/);
   if ( !mdy ) return false;
   // Use Javascript date constructor to check the date
   var dt = new Date(mdy[3], mdy[1]-1, mdy[2]);
   if ( isNaN(dt) ) return false;
   // JS allows 12/99/2008; see if month or year changed
   return +mdy[1] == dt.getMonth()+1 && +mdy[3] == dt.getFullYear();
 },
 "Please enter a valid date in the form mm/dd/yyyy."
);