Hi,

>I have a ASP.Net webform that contains a textbox where a user should enter a date in mm/dd/yy format.
>
>How can I validate that the user enter a good date?

Take a look at : http://www.codeguru.com/csharp/.net/net_general/netframeworkclasses/article.php/c7547/

Jist of it is:

static bool ValidateDate(String date, String format)
{
   try
   {
      System.Globalization.DateTimeFormatInfo dtfi = new
             System.Globalization.DateTimeFormatInfo();
      dtfi.ShortDatePattern = format;
      DateTime dt = DateTime.ParseExact(date, "d", dtfi);
   }
   catch(Exception)
   {
      return false;
   }
   return true;
}

HTH,
Viv