function validate(formvalue)
{
 if (formvalue.email.value == "")
  {
    alert("You must enter email ID to register.");
    return (false);
  }
  email = formvalue.email.value;
  if(!isEmail(email))
  {
    		alert("Please enter valid email ID to register.");
    		return (false);
  }
  	if(email.match("nio\.org") == null)
  	{
    		alert("Sorry, the email ID is not valid NIO email.");
    		return (false);
  	}
}

function isEmail(s)
{
  	// there must be >= 1 character before @, so we //
  	// start looking at character position 1        //
  	// (i.e. second character)                      //
  	var i = 1;
  	var sLength = s.length;
  	// look for @ //
  	while ((i < sLength) && (s.charAt(i) != "@"))
  	{ i++;
  	}
  	if ((i >= sLength) || (s.charAt(i) != "@")) return false;
  	else i += 2;
  	// look for . //
  	while ((i < sLength) && (s.charAt(i) != "."))
	{ i++
  	}

  	// there must be at least one character after the . //
  	if ((i >= sLength - 1) || (s.charAt(i) != ".")) return false;
	else return true;
}
