PHP AJAX Poll Example

📊 PHP AJAX Poll Example

A poll lets users vote on a question, and using AJAX and PHP, we can update the poll results dynamically without reloading the page.

1️⃣ Database Setup

Table: poll

id	option	votes
1	Option A	0
2	Option B	0
3	Option C	0

2️⃣ PHP Script to Display Poll (`poll.php`)

<?php
$conn = new mysqli("localhost", "root", "", "test_db");
if ($conn->connect_error) die("Connection failed: " . $conn->connect_error);

// Fetch poll options
$sql = "SELECT * FROM poll";
$result = $conn->query($sql);

echo '<h3>Vote for your favorite option:</h3>';
echo '<form id="pollForm">';
while ($row = $result->fetch_assoc()) {
echo '<input type="radio" name="option" value="'.$row['id'].'"> '.$row['option'].'<br>';
}
echo '<button type="button" onclick="submitVote()">Vote</button>';
echo '</form>';
echo '<div id="pollResult"></div>';

$conn->close();
?>

<?php

$conn = new mysqli("localhost", "root", "", "test_db");

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

// Fetch poll options

$sql = "SELECT * FROM poll";

$result = $conn->query($sql);

echo '<h3>Vote for your favorite option:</h3>';

echo '<form id="pollForm">';

while ($row = $result->fetch_assoc()) {

echo '<input type="radio" name="option" value="'.$row['id'].'"> '.$row['option'].'<br>';

}

echo '<button type="button" onclick="submitVote()">Vote</button>';

echo '</form>';

echo '<div id="pollResult"></div>';

$conn->close();

3️⃣ PHP Script to Process Vote (`vote.php`)

<?php
$conn = new mysqli("localhost", "root", "", "test_db");
if ($conn->connect_error) die("Connection failed: " . $conn->connect_error);

if(isset($_POST['option'])) {
$option = intval($_POST['option']);
$sql = "UPDATE poll SET votes = votes + 1 WHERE id = $option";
$conn->query($sql);

// Fetch updated results
$sql = "SELECT * FROM poll";
$result = $conn->query($sql);
echo '<h3>Poll Results:</h3><ul>';
while($row = $result->fetch_assoc()) {
echo '<li>'.$row['option'].' - '.$row['votes'].' votes</li>';
}
echo '</ul>';
}

$conn->close();
?>

<?php

$conn = new mysqli("localhost", "root", "", "test_db");

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

if(isset($_POST['option'])) {

$option = intval($_POST['option']);

$sql = "UPDATE poll SET votes = votes + 1 WHERE id = $option";

$conn->query($sql);

// Fetch updated results

$sql = "SELECT * FROM poll";

$result = $conn->query($sql);

echo '<h3>Poll Results:</h3><ul>';

while($row = $result->fetch_assoc()) {

echo '<li>'.$row['option'].' - '.$row['votes'].' votes</li>';

}

echo '</ul>';

}

$conn->close();

4️⃣ HTML + JavaScript (`index.html`)

<!DOCTYPE html>
<html>
<head>
<title>PHP AJAX Poll</title>
<script>
function submitVote() {
var radios = document.getElementsByName('option');
var selected = null;
for (var i=0; i<radios.length; i++) {
if(radios[i].checked) selected = radios[i].value;
}
if(selected == null){
alert("Please select an option.");
return;
}

var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if(this.readyState == 4 && this.status == 200){
document.getElementById('pollResult').innerHTML = this.responseText;
}
};
xhttp.open("POST", "vote.php", true);
xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhttp.send("option=" + selected);
}
</script>
</head>
<body>
<h2>Live Poll Using PHP & AJAX</h2>
<div id="pollContainer">
<?php include 'poll.php'; ?>
</div>
</body>
</html>

<!DOCTYPE html>

<html>

<head>

function submitVote() {

var radios = document.getElementsByName('option');

var selected = null;

for (var i=0; i<radios.length; i++) {

if(radios[i].checked) selected = radios[i].value;

}

if(selected == null){

alert("Please select an option.");

return;

}

var xhttp = new XMLHttpRequest();

xhttp.onreadystatechange = function() {

if(this.readyState == 4 && this.status == 200){

document.getElementById('pollResult').innerHTML = this.responseText;

}

};

xhttp.open("POST", "vote.php", true);

xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");

xhttp.send("option=" + selected);

}

</script>

</head>

<body>

<h2>Live Poll Using PHP & AJAX</h2>

<?php include 'poll.php'; ?>

</div>

</body>

</html>

5️⃣ How It Works

User selects an option and clicks Vote.
submitVote() sends the selected option to vote.php using AJAX POST.
PHP updates the votes in MySQL and returns updated results.
JavaScript updates the poll results dynamically in div#pollResult.

6️⃣ Key Points

AJAX allows real-time update of poll results without reloading.
Use POST method to send user votes securely.
Always validate and sanitize inputs in PHP.
Can be enhanced with charts or percentages for better UX.
Suitable for website polls, surveys, or voting apps.

PHP AJAX Poll Example