how to exact output in ajax - php

Question

My code is working well but problem in output. I don't get exact output that i want.
$("#search_traveller_button").click(function(){
$.ajax({
url: "index.php?act=checkSessionUser",
type: "POST",
cache: false,
success: function(data){
console.log(data);
},
error:function(){
console.log("Error: Unknown Error");
}
});
});
PHP code:
<?php
if(isset($_SESSION['userId'])) {
echo "1";
} else {
echo "0";
}
?>
output in success gives also html code, why?
0 </div>
<footer class="nav navbar-inverse">
...........
</footer>
</body>
</html>
I want in my output only 0 in a variable, not html code.

Answer 1

The problem is with your php code here's an example php code. You need to encode as JSON this lets jQuery .success or .fail have a JSON response as a callback.
What I am doing is I have a php file and a js file.
PHP
<?php
$name = $_POST['name'];
$email = $_POST['email'];
$msg = $_POST['message'];
$nospace_name = trim($_POST['name']);
$nospace_email = trim($_POST['email']);
$nospace_message = trim($_POST['message']);
if (empty($nospace_name))
$errors['name'] = "Name field is required.";
if (empty($nospace_email))
$errors['email'] = "Email field is required.";
if (empty($nospace_message))
$errors['message'] = "I would love to see your message.";
if (!empty($nospace_email) && !preg_match("^[a-zA-Z0-9_\-\.]+#[a-zA-Z0-9\-]+\.[a-zA-Z0-9\-\.]+$^", $nospace_email))
$errors['bad_email'] = "Please enter a valid email address";
// if there are any errors in our errors array, return a success boolean of false
if (!empty($errors)) {
// if there are items in our errors array, return those errors
$data['success'] = false;
$data['errors'] = $errors;
}
else {
// if there are no errors process our form, then return a message
// prepare message to be sent
$to = "me#example.com";
$subject = "Website Contact Form: ".$name;
// build the message
$message = "Name: ".$name."\n\n";
$message .= "Email: ".$email."\n\n";
$message .= "Message: ".$msg;
// send it
$mailSent = mail($to, $subject, $message, $headers);
// check if mail was sent successfully
if (!$mailSent) {
$errors['unknown_error'] = "Something went wrong...Please try again later";
$data['success'] = false;
$data['errors'] = $errors;
}
else {
// show a message of success and provide a true success variable
$data['success'] = true;
$data['message'] = "Thank you for contacting me, I\'ll get back to you soon!";
}
}
// return all our data to an AJAX call
echo json_encode($data);
?>
JS
$(function() {
$("#contactForm").submit(function(e) {
$.ajax({
type: 'POST',
url: 'contact.php',
data: $(this).serialize(),
dataType: "json"
})
.done(function(msg) {
if (msg.success == true) {
response = '<div class="success">' + msg.message + '</div>';
$contactform.hide();
}
else {
response = '<div class="error">' + msg.errors + '</div>';
}
// Show response message.
$("#contactForm").prepend(response);
})
e.preventDefault();
});
});

Answer 2

Because the php is successful in returning a result.
The error would be triggered if the php failed to return.
If you want your Ajax handler to do something different if not logged in either specify in the Ajax handler (not recommended) or do it on the server side (in the php) returning what you want if they are not authenticated.
$("#search_traveller_button").click(function(){
$.ajax({
url: "index.php?act=checkSessionUser",
type: "POST",
cache: false,
success: function(data){
if (data==1){
console.log ("yeah it worked")
}else {
console.log ("error")
}
});
});