AJAX没有从JS调用php文件？

The Problem:

Hello, I made sure that my PHP file is working, but unfortunately my ajax code is not. I placed the ajax inside a javascript function to call the file when needed, but when the function is executed nothing happens.

The Code:

Here is my JS Code:

function countdownEnded() {
    //make serverscreen dissapear
        document.getElementById('serverScreenWrapper').style.display = 'none';
        document.getElementById('serverScreenWrapper').style.opacity = '0';
        document.getElementById("cashOutNumTwo").style.right = '150%';
        document.getElementById("cashOutNumOne").style.right = '150%';
//start Timer
        setInterval(gameTimer.update, 1000);
//make player move again
        socket.emit('4');
        socket.emit('6');
//make game appear
        document.getElementById('gameAreaWrapper').style.opacity = 1;
//play sound
        document.getElementById('spawn_cell').play();
//cut 5 cents from account - php function
        $.ajax({
        type: "POST",
        url: 'http://cashballz.net/game/5game/subtract5.php',
        data: { },
        success: function (data) {
            alert(data);
        }
    });
}

My HTML:

<script src="//code.jquery.com/jquery-2.2.0.min.js"></script>

And even my PHP:

<?php
session_start();

$servername = "localhost";
$username = "myName";
$password = "myPass*";
$dbname = "myDBname";
$cash_amount = $_SESSION['cash_amount'];

// Create connection

$userid = $_SESSION['id'];

// You must enter the user's id here. /\

$conn = new mysqli($servername, $username, $password, $dbname);
// Check connection

if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// Fetch the existing value of the cash_amount against that particular user here. You can use the SELECT cash_amount from users where userid = $userid

$_SESSION['cash_amount'] -= 0.05;

$sql = "UPDATE users SET cash_amount = cash_amount - 0.05 WHERE id = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param('s', $userid);
$result = $stmt->execute();


if($result)
{
   echo "5 cents have been subtracted!";
}
else
{
   echo mysqli_error($conn);
   session_start();
   session_unset();
   session_destroy();
}

$conn->close();
?>

Conclusion:

I don't understand why my file isn't being called.

I have JQuery and i researched quite a bit on AJAX and looked at other similiar questions on this site.

I went to the file link and it works perfectly so i am pretty sure this is a javascript error.

I am great at JS, but a beginner to PHP and JQuery.

Thanks for all your help.

Try modifying your ajax call to include an error handlers. As an example:

$.ajax({
    type: "POST",
    url: 'http://cashballz.net/game/5game/subtract5.php',
    data: { },
    success: function (data) {
        alert(data);
    },
    error: function(data) {
        alert(data);
    }

PHP: header('Access-Control-Allow-Origin: *'); to allow cross domain access.