如何使用PHP实现微信小程序的任务进度功能？

<?php
session_start();

// 小程序登录接口
$url = "https://api.weixin.qq.com/sns/jscode2session?appid=YOUR_APPID&secret=YOUR_APPSECRET&js_code=JSCODE&grant_type=authorization_code";
$js_code = $_GET['code']; // 从小程序的登录接口获取到code
$url = str_replace("JSCODE", $js_code, $url);

// 发送请求获取用户OpenID
$result = file_get_contents($url);
$data = json_decode($result, true);
$openid = $data['openid'];

$_SESSION['openid'] = $openid;

echo $openid; // 返回OpenID给小程序
?>

CREATE TABLE tasks (
    id INT AUTO_INCREMENT PRIMARY KEY,
    openid VARCHAR(255),
    title VARCHAR(255),
    progress INT
);

<?php
session_start();
$openid = $_SESSION['openid'];

$title = $_POST['title']; // 从小程序的表单中获取任务标题

// 将任务数据插入到数据库中
$conn = new mysqli("localhost", "username", "password", "database");
$sql = "INSERT INTO tasks (openid, title, progress) VALUES ('$openid', '$title', 0)";
$conn->query($sql);

echo "任务创建成功";
?>

<?php
session_start();
$openid = $_SESSION['openid'];

$taskId = $_POST['taskId']; // 从小程序的表单中获取要更新的任务ID
$progress = $_POST['progress']; // 从小程序的表单中获取任务的新进度

// 更新任务的进度到数据库中
$conn = new mysqli("localhost", "username", "password", "database");
$sql = "UPDATE tasks SET progress = $progress WHERE id = $taskId AND openid = '$openid'";
$conn->query($sql);

echo "任务进度更新成功";
?>