如何在PHP中插入多个HTML检查表值？

<?php
// 连接数据库
$servername = "数据库服务器地址";
$username = "数据库用户名";
$password = "数据库密码";
$dbname = "数据库名";

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

// 获取表单提交的值并插入数据库
if ($_SERVER["REQUEST_METHOD"] == "POST") {
    foreach ($_POST as $key => $value) {
        // 过滤和准备插入的值
        $key = mysqli_real_escape_string($conn, $key);
        $value = mysqli_real_escape_string($conn, $value);

        // 执行插入操作
        $sql = "INSERT INTO 表名 (字段1, 字段2) VALUES ('$key', '$value')";
        if ($conn->query($sql) === TRUE) {
            echo "插入成功";
        } else {
            echo "插入失败: " . $conn->error;
        }
    }
}

// 关闭数据库连接
$conn->close();
?>