如何在php中强制重新连接到我的数据库？

$servername = "数据库服务器地址";
$username = "用户名";
$password = "密码";
$dbname = "数据库名";

// 建立与数据库的连接
$conn = mysqli_connect($servername, $username, $password, $dbname);

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

// 检查连接状态
if (!mysqli_ping($conn)) {
    // 关闭当前连接
    mysqli_close($conn);
    
    // 重新建立连接
    $conn = mysqli_connect($servername, $username, $password, $dbname);
    
    // 检查重新连接是否成功
    if (!$conn) {
        die("重新连接失败: " . mysqli_connect_error());
    }
}

$sql = "SELECT * FROM 表名";
$result = mysqli_query($conn, $sql);

if (mysqli_num_rows($result) > 0) {
    // 处理查询结果
    while ($row = mysqli_fetch_assoc($result)) {
        echo "字段1: " . $row["字段1"] . ", 字段2: " . $row["字段2"] . "<br>";
    }
} else {
    echo "没有结果";
}

// 关闭连接
mysqli_close($conn);