function isValidEmail(address) {
   if (address != '' && address.search) {
      if (address.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1) return true;
      else return false;
   }
   
   // allow empty strings to return true - screen these with either a 'required' test or a 'length' test
   else return true;
}

function isAlphanumeric(string, ignoreWhiteSpace) {
   if (string.search) {
      if ((ignoreWhiteSpace && string.search(/[^\w\s]/) != -1) || (!ignoreWhiteSpace && string.search(/\W/) != -1)) return false;
   }
   return true;
}

// Check that a string contains only letters
function isAlphabetic(string, ignoreWhiteSpace) {
   if (string.search) {
      if ((ignoreWhiteSpace && string.search(/[^a-zA-Z\s]/) != -1) || (!ignoreWhiteSpace && string.search(/[^a-zA-Z]/) != -1)) return false;
   }
   return true;
}

// Check that a string contains only numbers
function isNumeric(string, ignoreWhiteSpace) {
   if (string.search) {
      if ((ignoreWhiteSpace && string.search(/[^\d\s]/) != -1) || (!ignoreWhiteSpace && string.search(/\D/) != -1)) return false;
   }
   return true;
}

// Remove leading and trailing whitespace from a string
function trimWhitespace(string) {
   var newString  = '';
   var substring  = '';
   beginningFound = false;
   
   // copy characters over to a new string
   // retain whitespace characters if they are between other characters
   for (var i = 0; i < string.length; i++) {
      
      // copy non-whitespace characters
      if (string.charAt(i) != ' ' && string.charCodeAt(i) != 9) {
         
         // if the temporary string contains some whitespace characters, copy them first
         if (substring != '') {
            newString += substring;
            substring = '';
         }
         newString += string.charAt(i);
         if (beginningFound == false) beginningFound = true;
      }
      
      // hold whitespace characters in a temporary string if they follow a non-whitespace character
      else if (beginningFound == true) substring += string.charAt(i);
   }
   return newString;
}

// Remove characters that might cause security problems from a string 
function removeBadCharacters(string) {
   if (string.replace) {
      string.replace(/[<>\"\'%;\)\(&\+]/, '');
   }
   return string;
}

// Remove all spaces from a string
function removeSpaces(string) {
   var newString = '';
   for (var i = 0; i < string.length; i++) {
      if (string.charAt(i) != ' ') newString += string.charAt(i);
   }
   return newString;
}

function isZeroLength(string){
	if(trimWhitespace(string) == '') return true;
	else return false;
}

function isItemAdded(oListBox){
	if(oListBox.length < 1) return false;
	else return true;
}

function isItemSelected(oDropDown){
	if(oDropDown.length < 2 || oDropDown.selectedIndex < 1 || oDropDown.options[oDropDown.selectedIndex].value < 1) return false;
	else return true;
}

function isItemChecked(ids)
{
	for(i=0;i<ids.length;i++)
	{
		if(document.getElementById(ids[i]) && isChecked(document.getElementById(ids[i]))) return true;
	}
	return false;
}

function showError(id){
	if(document.getElementById(id)) document.getElementById(id).className = 'mandatoryCharRed';
}

function hideError(id){
	if(document.getElementById(id)) document.getElementById(id).className = 'mandatoryChar';
}

function isChecked(oCheckBox){
	if(oCheckBox.checked) return true;
	else return false;
}
