如何使用PHP开发微信小程序的任务评价功能？

CREATE TABLE `task_evaluation` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `task_id` int(11) NOT NULL,
  `user_id` int(11) NOT NULL,
  `rating` int(11) NOT NULL,
  `comment` text NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

<?php
// 接收评价数据
$task_id = $_POST['task_id'];
$user_id = $_POST['user_id'];
$rating = $_POST['rating'];
$comment = $_POST['comment'];

// 连接数据库
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "myDB";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
  die("数据库连接失败: " . $conn->connect_error);
}

// 插入评价数据到数据库
$sql = "INSERT INTO task_evaluation (task_id, user_id, rating, comment)
        VALUES ('$task_id', '$user_id', '$rating', '$comment')";
if ($conn->query($sql) === TRUE) {
  echo "评价提交成功";
} else {
  echo "评价提交失败: " . $conn->error;
}

$conn->close();
?>

<?php
// 查询评价数据
$task_id = $_GET['task_id'];

// 连接数据库
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "myDB";
$conn = new mysqli($servername, $username, $password, $dbname);
if ($conn->connect_error) {
  die("数据库连接失败: " . $conn->connect_error);
}

// 查询评价数据
$sql = "SELECT * FROM task_evaluation WHERE task_id = '$task_id'";
$result = $conn->query($sql);

// 将评价数据转换为JSON格式，并输出给小程序客户端
$evaluations = array();
if ($result->num_rows > 0) {
  while($row = $result->fetch_assoc()) {
    $evaluation = array(
      'id' => $row['id'],
      'task_id' => $row['task_id'],
      'user_id' => $row['user_id'],
      'rating' => $row['rating'],
      'comment' => $row['comment']
    );
    array_push($evaluations, $evaluation);
  }
}
echo json_encode($evaluations);

$conn->close();
?>