mysql连接设置中文php

<?php
$mysqli = new mysqli("localhost", "username", "password", "mydatabase");
if ($mysqli->connect_error) {
    die("连接失败: " . $mysqli->connect_error);
}
$mysqli->set_charset("utf8mb4");

$sql = "SELECT * FROM mytable";
$result = $mysqli->query($sql);

if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "ID: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
    }
} else {
    echo "0 结果";
}
$mysqli->close();
?>

<?php
$dsn = "mysql:host=localhost;dbname=mydatabase;charset=utf8mb4";
try {
    $pdo = new PDO($dsn, "username", "password");
    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    $sql = "SELECT * FROM mytable";
    $stmt = $pdo->query($sql);

    while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
        echo "ID: " . $row["id"]. " - Name: " . $row["name"]. "<br>";
    }
} catch (PDOException $e) {
    echo "连接失败: " . $e->getMessage();
}
?>