PHP を使用して簡単なブログ システムを作成する方法

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

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

<?php
// 用户注册
if ($_SERVER["REQUEST_METHOD"] == "POST" && isset($_POST["register"])) {
    $username = $_POST["username"];
    $password = $_POST["password"];

    // 插入用户数据
    $sql = "INSERT INTO user (username, password) VALUES ('$username', '$password')";
    if ($conn->query($sql) === TRUE) {
        echo "注册成功";
    } else {
        echo "注册失败: " . $conn->error;
    }
}

// 用户登录
if ($_SERVER["REQUEST_METHOD"] == "POST" && isset($_POST["login"])) {
    $username = $_POST["username"];
    $password = $_POST["password"];

    // 检查用户数据
    $sql = "SELECT * FROM user WHERE username='$username' AND password='$password'";
    $result = $conn->query($sql);

    if ($result->num_rows > 0) {
        echo "登录成功";
    } else {
        echo "用户名或密码错误";
    }
}
?>

<?php
// 发表博客
if ($_SERVER["REQUEST_METHOD"] == "POST" && isset($_POST["publish"])) {
    $title = $_POST["title"];
    $content = $_POST["content"];
    $user_id = $current_user_id; // 假设当前登录用户的ID为$current_user_id

    // 插入博客数据
    $sql = "INSERT INTO blog (title, content, user_id) VALUES ('$title', '$content', '$user_id')";
    if ($conn->query($sql) === TRUE) {
        echo "发表成功";
    } else {
        echo "发表失败: " . $conn->error;
    }
}

// 编辑博客
if ($_SERVER["REQUEST_METHOD"] == "POST" && isset($_POST["edit"])) {
    $blog_id = $_POST["blog_id"];
    $title = $_POST["title"];
    $content = $_POST["content"];

    // 更新博客数据
    $sql = "UPDATE blog SET title='$title', content='$content' WHERE id='$blog_id'";
    if ($conn->query($sql) === TRUE) {
        echo "修改成功";
    } else {
        echo "修改失败: " . $conn->error;
    }
}
?>

<?php
// 博客列表展示
$sql = "SELECT * FROM blog";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
    while($row = $result->fetch_assoc()) {
        echo "博客标题: " . $row["title"] . "<br>";
        echo "博客内容: " . $row["content"] . "<br>";
        echo "发布时间: " . $row["create_time"] . "<br>";

        // 获取评论
        $blog_id = $row["id"];
        $comment_sql = "SELECT * FROM comment WHERE blog_id='$blog_id'";
        $comment_result = $conn->query($comment_sql);
        if ($comment_result->num_rows > 0) {
            echo "评论列表: <br>";
            while($comment_row = $comment_result->fetch_assoc()) {
                echo "评论内容: " . $comment_row["content"] . "<br>";
                echo "评论时间: " . $comment_row["create_time"] . "<br>";
            }
        } else {
            echo "暂无评论<br>";
        }

        echo "<br>";
    }
} else {
    echo "暂无博客";
}

// 博客评论
if ($_SERVER["REQUEST_METHOD"] == "POST" && isset($_POST["comment"])) {
    $content = $_POST["content"];
    $blog_id = $_POST["blog_id"];
    $user_id = $current_user_id; // 假设当前登录用户的ID为$current_user_id

    // 插入评论数据
    $sql = "INSERT INTO comment (content, blog_id, user_id) VALUES ('$content', '$blog_id', '$user_id')";
    if ($conn->query($sql) === TRUE) {
        echo "评论成功";
    } else {
        echo "评论失败: " . $conn->error;
    }
}
?>