<!--

function trim(strValue) {
	//trim the leading spaces
	while(strValue.charAt(0) == ' ') strValue = strValue.substring(1, strValue.length);
	//trim the trailing spaces
	while(strValue.charAt(strValue.length-1) == ' ') strValue = strValue.substring(0, strValue.length-1);
	//return the string to the user
	return strValue;
}

function isNumeric(input) {
    if (input.length == 0)
        return false;
    for (var i=0;i < input.length;i++)
        if (((input.substring(i,i+1) < '0') || (input.substring(i,i+1) > '9')) && input.substring(i, i+1) != '.' && input.substring(i, i+1) != '-')
            return false;
    
    return true;

}

function isEmpty(input) {
	if (trim(input) == "") 
		return true; 
	else 
		return false;
}

function isSelected(lstInput) {
	//first test to see if the select list has the "muliple" attribute selected
	if (lstInput.type == "select-one") { //this is a single select list
		if (lstInput.options[lstInput.selectedIndex].value == "" || lstInput.options[lstInput.selectedIndex].value == "error")
			return false;
		else
			return true;
	} else if (lstInput.type == "select-multiple") { //this is a multiple select list
		if (lstInput.selectedIndex == -1) //nothing was selected
			return false;
		else
			return true;
	}
}
	
function isEmail(emailStr) {
	/* The following pattern is used to check if the entered e-mail address
   fits the user@domain format.  It also is used to separate the username
   from the domain. */
	var emailPat=/^(.+)@(.+)$/
	/* The following string represents the pattern for matching all special
   characters.  We don't want to allow special characters in the address. 
   These characters include ( ) < > @ , ; : \ " . [ ]    */
	var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
	/* The following string represents the range of characters allowed in a 
   username or domainname.  It really states which chars aren't allowed. */
	var validChars="\[^\\s" + specialChars + "\]"
	/* The following pattern represents the range of characters allowed as
   the first character in a valid username or domain.  I just made it
   the same as above, but if you want to add a different constraint,
   you would change it here. */
	var firstChars=validChars
	/* The following pattern applies if the "user" is a quoted string (in
   which case, there are no rules about which characters are allowed
   and which aren't; anything goes).  E.g. "jiminy cricket"@disney.com
   is a legal e-mail address. */
	var quotedUser="(\"[^\"]*\")"
	/* The following pattern applies for domains that are IP addresses,
   rather than symbolic names.  E.g. joe@[123.124.233.4] is a legal
   e-mail address. NOTE: The square brackets are required. */
	var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
	/* The following string represents at atom (basically a series of
   non-special characters.) */
	var atom="(" + firstChars + validChars + "*" + ")"
	/* The following string represents one word in the typical username.
   For example, in john.doe@somewhere.com, john and doe are words.
   Basically, a word is either an atom or quoted string. */
	var word="(" + atom + "|" + quotedUser + ")"
	// The following pattern describes the structure of the user
	var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
	/* The following pattern describes the structure of a normal symbolic
   domain, as opposed to ipDomainPat, shown above. */
	var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")


	/* Finally, let's start trying to figure out if the supplied address is
   valid. */

	/* Begin with the course pattern to simply break up user@domain into
   different pieces that are easy to analyze. */
	var matchArray=emailStr.match(emailPat)
	if (matchArray==null) {
  	/* Too many/few @'s or something; basically, this address doesn't
     even fit the general mould of a valid e-mail address. */
		//alert("Email address seems incorrect (check @ and .'s)")
		return false
	}
	var user=matchArray[1]
	var domain=matchArray[2]

	// See if "user" is valid 
	if (user.match(userPat)==null) {
    // user is not valid
   // alert("The username doesn't seem to be valid.")
    return false
	}
	/* if the e-mail address is at an IP address (as opposed to a symbolic
   host name) make sure the IP address is valid. */
	var IPArray=domain.match(ipDomainPat)
	if (IPArray!=null) {
    // this is an IP address
	  for (var i=1;i<=4;i++) {
	    if (IPArray[i]>255) {
	      //alert("Destination IP address is invalid!")
				return false
	    }
    }
    return true
	}

	// Domain is symbolic name
	var domainArray=domain.match(domainPat)
	if (domainArray==null) {
		//alert("The domain name doesn't seem to be valid.")
    return false
	}
	/* domain name seems valid, but now make sure that it ends in a
   three-letter word (like com, edu, gov) or a two-letter word,
   representing country (uk, nl).
   If there's a country code at the end of the address, the full domain
   must include a hostname and category (e.g. host.co.uk or host.pub.nl).
   If it ends in a .com or something, make sure there's a hostname.*/

	/* Now we need to break up the domain to get a count of how many atoms
   it consists of. */
	var atomPat=new RegExp(atom,"g")
	var domArr=domain.match(atomPat)
	var len=domArr.length
	if (domArr[domArr.length-1].length<2 || domArr[domArr.length-1].length>4) {
   // the address must end in a two letter thru four letter word.
  // alert("The address must end in a three-letter domain, or two letter country.")
   return false
	}

	/* If it ends in a country code, we want to make sure there are at
   least 2 atoms preceding it (representing host and category (i.e.
   com, gov, etc.)) */
   /*
	if (domArr[domArr.length-1].length==2 && len<3) {
   var errStr="This address ends in two characters, which is a country" 
   return false
	}
	*/
	
	/* If it just ends in .com, .gov, etc., make sure there's a host name.
   This case can never actually happen because earlier checks take
   care of this implicitly, but we'll do it anyway. */
	if (domArr[domArr.length-1].length==3 && len<2) {   	
   	return false
	}
	// If we've gotten this far, everything's valid!
	return true;
}
function isDate(dateStr) {
	// Checks for the following valid date formats:
	// MM/DD/YY   MM/DD/YYYY   MM-DD-YY   MM-DD-YYYY
	// Also separates date into month, day, and year variables

	//var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{2}|\d{4})$/;

	// To require a 4 digit year entry, use this line instead:
	var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{4})$/;

	var matchArray = dateStr.match(datePat); // is the format ok?
	if (matchArray == null) {
		//alert("Date is not in a valid format.");
		return false;
	}
	month = matchArray[1]; // parse date into variables
	day = matchArray[3];
	year = matchArray[4];
	if (month < 1 || month > 12) { // check month range
		//alert("Month must be between 1 and 12.");
		return false;
	}
	if (day < 1 || day > 31) {
		//alert("Day must be between 1 and 31.");
		return false;
	}
	if ((month==4 || month==6 || month==9 || month==11) && day==31) {
		//alert("Month "+month+" doesn't have 31 days!")	
		return false
	}
	if (month == 2) { // check for february 29th
		var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
		if (day>29 || (day==29 && !isleap)) {
			//alert("February " + year + " doesn't have " + day + " days!");
			return false;
   	}
	}
	return true;  // date is valid
}

//--->