// use for Login Form
function loginForm()
{
 if(document.loginform.userid.value == "")
 {
 alert("Please enter Username");
 return false;
 }
 if(document.loginform.pwd.value == "")
 {
 alert("Please enter Password");
 return false;
 }
 return true;
}

// use for change password form
function checkChangePasswordForm()
{
  if(document.form1.old_pwd.value == "")
  {
   alert("Please enter old password");
   return false;
  }
  if(document.form1.new_pwd.value == "")
  {
  alert("Please enter new password");
  return false;
  }
  if(document.form1.confirm_pwd.value == "")
  {
  alert("Please enter confirm password");
  return false;
  }
  if(document.form1.new_pwd.value != document.form1.confirm_pwd.value)
  {
  alert("New Password does not match with Confirm Password");
  return false;
  }
  return true;
}


function luhn_check(number) {

  // Strip any non-digits (useful for credit card numbers with spaces and hyphens)
  var number=number.replace(/\D/g, '');

  // Set the string length and parity
  var number_length=number.length;
  var parity=number_length % 2;

  // Loop through each digit and do the maths
  var total=0;
  for (i=0; i < number_length; i++) {
    var digit=number.charAt(i);
    // Multiply alternate digits by two
    if (i % 2 == parity) {
      digit=digit * 2;
      // If the sum is two digits, add them together (in effect)
      if (digit > 9) {
        digit=digit - 9;
      }
    }
    // Total up the digits
    total = total + parseInt(digit);
  }

  // If the total mod 10 equals 0, the number is valid
  if (total % 10 == 0) {
    return true;
  } else {
    return false;
  }

}
function luhn_check_notify(number) {
	number = number.replace(/[\.\-\ ]/g, '');
	if(isNaN(number))
	{ return false; }
  if (luhn_check(number)) {
    return true;
  } else {
    return false;
  }
}