.comment.header {
   position: sticky;
   position: -webkit-sticky; /* Safari */
   top: 0;
}

message.replace(regex, function (_match, name, id, _offset, _string) {
    return `<a href="user.php?username=${id}">${name}</a>`;
});

$('tr').each((i, ele) => {
    $(ele).on('click', function(e) {
        let el = this;
        // do something
    });
});

$('table').on('click', 'tr', function(e) {
    let el = e.currentTarget;
    // do something
});

class View {
    private $master_content;
    // some private attribute...

    public function __construct($master, $nav, $sidebar, $title, $part) {
        $this->load($master,$nav,$sidebar);
        ob_start();
    }

    private function load($master, $nav, $sidebar) {
        ob_start();
        include($master);
        $this->master_content = ob_get_contents();
        ob_end_clean();
        // load navbar and sidebar...
    }
    
    public function render() {
        $content = ob_get_contents();
        ob_end_clean();
        
        echo strtr($this->master_content, array(
            // ...
            '{content}' => $content
        ));
        @ob_flush();
        flush();
    }
};

filter_var($variable [, $filter = FILTER_DEFAULT [, $options ]])

SELECT `post`.*, `user`.name FROM `post` INNER JOIN `user`
ON `post`.username = `user`.username

setInterval(() => {
    axios.request({
        url: "ajax/notification.php?fetch",
        method: "GET"
    }).done((res) => {
        setNotificationCounter(res.data);
    }).catch((err) => {
        console.error(err);
    });
});

axios.defaults.withCredentials = true;

axios.interceptors.request.use(function (config) {
    var crypto = window.crypto || window.msCrypto;
    let csrfToken = btoa(String(crypto.getRandomValues(new Uint32Array(1))[0]));
    document.cookie = `${axios.defaults.xsrfCookieName}=${csrfToken}; max-age=10; path=/`;
    return config;
}, function (error) {
    return Promise.reject(error);
});

var root = "./";
var useHash = true;
var hash = "#";
let router = new Navigo(root, useHash, hash);

router.on({
    '/post': function () {
        render('post');
    },
    '/post/:id': function () {
        render('post', params.id);
    },
    '/user/:username': function () {
        render('user', params.username)
    }
}).resolve();

router.hooks({
    before: (done, params) => {
        resetMenu();
        done();
    },
    after: params => {
        scrollTop();
    }
});

<a href="/post" data-navigo>文章列表</a>

router.navigate("/post")

router.updatePageLinks()