// whitespace characters
var whitespace = " \t\n\r";

// Check whether string s is empty.
function isEmpty(s)
{   return ((s == null) || (s.length == 0));
}


// Returns true if string s is empty or
// whitespace characters only.

function isWhitespace (s){
	var i;

    // Is s empty?
    if (isEmpty(s)) return true;

    // Search through string's characters one by one
    // until we find a non-whitespace character.
    // When we do, return false; if we don't, return true.

    for (i = 0; i < s.length; i++)
    {
	// Check that current character isn't whitespace.
	var c = s.charAt(i);

	if (whitespace.indexOf(c) == -1) return false;
    }
    // All characters are whitespace.
    return true;
}


function isValidEmailAddress(str) {
  if (window.RegExp) {
	  var reg1 = /^(([^<>()[\]\\.,;:\s@\"]+(\.[^<>()[\]\\.,;:\s@\"]+)*)|(\".+\"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
	  if (reg1.test(str)) {
      return true;
    }
    return false;
  } else {
    return ( str.indexOf("@") >= 0 );
  }
}