PHP Oist将一个下拉菜单中的两个变量转换为Mysql

<form method="POST" action="process.php">
  <select name="variable1" id="variable1">
    <option value="value1">Value 1</option>
    <option value="value2">Value 2</option>
    <option value="value3">Value 3</option>
  </select>
  
  <select name="variable2" id="variable2">
    <option value="option1">Option 1</option>
    <option value="option2">Option 2</option>
    <option value="option3">Option 3</option>
  </select>
  
  <input type="submit" value="Submit">
</form>

document.querySelector('form').addEventListener('submit', function(e) {
  e.preventDefault(); // 阻止表单提交
  
  var variable1 = document.getElementById('variable1').value;
  var variable2 = document.getElementById('variable2').value;
  
  // 将变量传递给PHP脚本
  var xhr = new XMLHttpRequest();
  xhr.open('POST', 'process.php', true);
  xhr.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
  xhr.onload = function() {
    // 处理响应
    if (xhr.status === 200) {
      console.log(xhr.responseText);
    }
  };
  xhr.send('variable1=' + variable1 + '&variable2=' + variable2);
});

<?php
$variable1 = $_POST['variable1'];
$variable2 = $_POST['variable2'];

// 连接到MySQL数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database";

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

// 检查连接是否成功
if ($conn->connect_error) {
  die("连接失败: " . $conn->connect_error);
}

// 将变量插入到数据库中
$sql = "INSERT INTO table_name (column1, column2) VALUES ('$variable1', '$variable2')";

if ($conn->query($sql) === TRUE) {
  echo "数据插入成功";
} else {
  echo "Error: " . $sql . "<br>" . $conn->error;
}

$conn->close();
?>