function isNumeric(sText)
{
   var ValidChars = "0123456789.";
   var IsNumber=true;
   var Char;
   if (sText.length == 0)
   	return false;
 
   for (i = 0; i < sText.length && IsNumber == true; i++) 
      { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         IsNumber = false;
         }
      }
   return IsNumber;
}

// ******************************************************************
// This function accepts a string variable and verifies if it is a
// proper date or not. It validates format matching either
// mm-dd-yyyy or mm/dd/yyyy. Then it checks to make sure the month
// has the proper number of days, based on which month it is.

// The function returns true if a valid date, false if not.
// ******************************************************************

function isDate(dateStr) {		
	var datePat = /^(\d{1,2})(\/|-)(\d{1,2})(\/|-)(\d{4})$/;
	var matchArray = dateStr.match(datePat); // is the format ok?
	
	if (matchArray == null) {
		alert("Please enter date as either mm/dd/yyyy or mm-dd-yyyy.");
		return false;
	}
	
	month = matchArray[1]; // p@rse date into variables
	day = matchArray[3];
	year = matchArray[5];
	
	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
}
function isPhoneNumber(phoneNumberTest)
{
	//var regExPhonePattern  = /\(?\d{3}\)?([-\/\.])\d{3}\1\d{4}/; 
	var regExPhonePattern  = /^[01]?[- .]?(\([2-9]\d{2}\)|[2-9]\d{2})[- .]?\d{3}[- .]?\d{4}/;
	if (phoneNumberTest.length > 0)
	{
		var result = regExPhonePattern.test(phoneNumberTest);
		return regExPhonePattern.test(phoneNumberTest);
	}
	else
	{
		return false;
	}
}
function isEmail(emailAddressTest)
{
	var regExEmailPattern = /^(("[\w-\s]+")|([\w-]+(?:\.[\w-]+)*)|("[\w-\s]+")([\w-]+(?:\.[\w-]+)*))(@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$)|(@\[?((25[0-5]\.|2[0-4][0-9]\.|1[0-9]{2}\.|[0-9]{1,2}\.))((25[0-5]|2[0-4][0-9]|1[0-9]{2}|[0-9]{1,2})\.){2}(25[0-5]|2[0-4][0-9]|1[0-9]{2}|[0-9]{1,2})\]?$)/i 
	if (emailAddressTest.length > 0)
		return regExEmailPattern.test(emailAddressTest);
	else
		return false;
}
/******************
function isPhoneNumber(s) 
{
     // Check for correct phone number
     rePhoneNumber = new RegExp(/(^\([1-9]\d{2}\)\s?\d{3}\-\d{4})|(\d{3}\-\d{3}\-\d{4})/);
 
     if (!rePhoneNumber.test(s)) {
          alert("Phone Number Must Be Entered As: (555) 555-1234");
          return false;
     }
	return true;
}
*************/
function isLettersOnly(sText)
{
   var ValidChars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
   var IsLetter=true;
   var Char;
   if (sText.length == 0)
   	return false;
 
   for (i = 0; i < sText.length && IsLetter == true; i++) 
      { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1) 
         {
         IsLetter = false;
         }
      }
   return IsLetter;
}