JRequest::getVar is keeping previous values even after refreshing - joomla3.0

Question

I am writing a mail function as a module in joomla 3. e mail works fine, but when i reload the page and insert a different email and send, but it seemed to return the previous email by JRequest::getVar function. Is there a way to solve this issue? thanks in advance..
this is the code i used:
<?php
defined('_JEXEC') or die('Direct Access to this location is not allowed.');
require_once(dirname(__FILE__) . DS . 'helper.php');
//declaration
$input = JFactory::getApplication()->input;
$form_send = $input->get('form_send', 'notsend');
$fanme = $input->get('firstName');
$lname = $input->get('lastinput');
$email = $input->get('email', 0 , 'STRING');
$mail=false;
$emailexist=false;
echo '<script>
var php_var = "chk is first:'.$email.'";
alert(php_var);
</script>';
switch ($form_send) {
case 'send':
if ((is_null($fanme) || is_null($lname) || is_null($email)) || (!filter_var($email, FILTER_VALIDATE_EMAIL))) {
echo '<div> Fields are empty or not valid. <br></div>';
} else {
$mail = ModLittleContactHelper::SendMail($email, $fanme, $lname);
echo '<script>
var php_var = "chk when mail sending:'.$email.'";
alert(php_var);
</script>';
$input = JFactory::getApplication();//i have tried $app also
$input ->setUserState('mod_mycontact.email', null);
}
//echo $respond
if (!$mail) {
echo 'Error sending email:';
require(JModuleHelper::getLayoutPath('mod_myecontact', 'default_tmpl'));
}else{
require(JModuleHelper::getLayoutPath('mod_mycontact', 'sendok_tmpl'));
break;
}
default:
require(JModuleHelper::getLayoutPath('mod_littlecontact', 'default_tmpl'));
unset($var);
}
?>
#Mario this is the helper code:
class ModLittleContactHelper{
public function SendMail($email, $fname, $lname) {
$body = "<p style='font-family:arial;font-size:20px;'>Hi " . $fname . " " . $lname . ",</p>";
$body.="<p style='font-family:arial;font-size:20px;'>Welcome to Crowd Logistics! Please verify your email address below.</p><br/><br/>";
$body.= "<hr><br/>";
$body.= "<p style='align:center;background-color:#40B3DF;font-family:arial;color:#FFFFFF;font-size:20px;'><a href='http://suriyaarachchi.com/crowdlogistics/index.php?option=com_content&view=article&id=192' target='_blank'>Verify " . $email . "</a></p>";
$body.= "<br/><hr><br/>";
$body.="<p style='text-align:right;font-family:arial;font-size:20px;'>Or, paste this link into your browser:<br/>";
$body.= "http://crowdlogistics/index.php?option=com_content&view=article&id=192<br/><br/>";
$body.= "Thanks.<br/>";
$body.= "CrowdLogistics</p><br/>";
$mailer = & JFactory::getMailer();
$mailer->setSender('info#crowdlogistics.com');
$mailer->addRecipient($email);
$mailer->setSubject('Mail from CrowdLogistics - Confirm your email');
$mailer->setBody($body);
$mailer->IsHTML(true);
$send = & $mailer->Send();
return $send;
}

Answer 1

Since you're trying to run your code on Joomla 3, there are a few things that are wrong. Below os your code, corrected where I was able to correct it. Now you have to test it in your module environment with the class being instantiated (in other words, test the below code in your module).
<?php
defined('_JEXEC') or die('Direct Access to this location is not allowed.');
require_once(dirname(__FILE__) . DIRECTORY_SEPARATOR . 'helper.php');
//declaration
$doc = JFactory::getDocument();
$app = JFactory::getApplication();
$input = $app->input;
$form_send = $input->get('form_send', 'notsend');
$fanme = $input->get('firstName');
$lname = $input->get('lastinput');
$email = $input->get('email', 0 , 'STRING');
$mail=false;
$emailexist=false;
$doc->addScriptDeclaration('
var php_var = "chk is first:'.$email.'";
alert(php_var);
');
switch ($form_send) {
case 'send':
if ((is_null($fanme) || is_null($lname) || is_null($email)) || (!filter_var($email, FILTER_VALIDATE_EMAIL))) {
echo '<div> Fields are empty or not valid. <br></div>';
} else {
$mail = ModLittleContactHelper::SendMail($email, $fanme, $lname);
$doc->addScriptDeclaration('
var php_var = "chk when mail sending:'.$email.'";
alert(php_var);');
$app->setUserState('mod_littlecontact.email', null);
}
//echo $respond
if (!$mail) {
echo 'Error sending email:';
require(JModuleHelper::getLayoutPath('mod_littlecontact', 'default_tmpl'));
break;
}else{
require(JModuleHelper::getLayoutPath('mod_littlecontact', 'sendok_tmpl'));
break;
}
default:
require(JModuleHelper::getLayoutPath('mod_littlecontact', 'default_tmpl'));
unset($var);
}
?>

Answer 2

First, JRequest class is deprecated in J3. You should use JInput:
$input = JFactory::getApplication()->input;
$your_var = $input->get('your_var');
Then, regarding the email, you probably need to unset the session variables when the success is achieved (mail sent), or in other words, when you don't need them any longer.
$app = JFactory::getApplication();
// your_var is the variable you want to unset
$app->setUserState('mod_your_module.your_var', null);
Hope it helps

Answer 3

you can use this code
$email = $input->get('email', 0 , 'STRING','');
4th argument for the default value,