php注册登录mysql

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

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

// 准备并绑定
$stmt = $conn->prepare("INSERT INTO users (username, password) VALUES (?, ?)");
$stmt->bind_param("ss", $username, $password);

$username = $_POST['username'];
$password = password_hash($_POST['password'], PASSWORD_DEFAULT);

$stmt->execute();

echo "新记录插入成功";

$stmt->close();
$conn->close();
?>

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

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

$username = $_POST['username'];
$password = $_POST['password'];

$stmt = $conn->prepare("SELECT password FROM users WHERE username=?");
$stmt->bind_param("s", $username);
$stmt->execute();
$stmt->bind_result($hashed_password);
$stmt->fetch();

if (password_verify($password, $hashed_password)) {
    echo "登录成功";
} else {
    echo "用户名或密码错误";
}

$stmt->close();
$conn->close();
?>