5: 投票

没有投票的投票是一个列表。在本章中，每个选项都变成一个表单，一个 POST route 接收投票，计数增加，重定向重新渲染页面。纯 HTTP，尚未使用 JavaScript：这个版本在任何浏览器中都能工作，所有功能都关闭。

5.1: The vote forms

In poll.phlo, turn each button in the choices view into a tiny form:

view choices:
<section.card>
	<foreach type_poll::records() AS $option>
		<form method=post action="/poll/vote/$option->id">
			<button>$option->option</button>
		</form>
	</foreach>
</section>

Each form posts to its own URL: /poll/vote/1, /poll/vote/2, and so on. The id travels in the path, so the form needs no hidden fields. Note the quotes around the action value: attributes containing variables or slashes must be quoted. The form: display: inline rule from chapter 3 keeps the buttons on one row.

Reload http://localhost/poll: looks identical, but every button now submits a form. Clicking one gives a 404, because the route does not exist yet.

5.2: POST 路由

在 poll.phlo 中添加路由，靠近 GET 路由：

route POST poll vote $id {
	if (!$option = type_poll::record(id: (int)$id)) return false
	type_poll::change('id=?', (int)$id, votes: $option->votes + 1)
	location('/poll')
}

从上到下阅读：

• route POST poll vote $id 匹配 POST /poll/vote/<id>。路径中的 $segment 是一个变量，可以在块内使用。
• type_poll::record(id: ...) 获取一条记录或返回 null。返回确切的 false 表示路由未命中：未知的 id 会被忽略，最终返回 404，而不是破坏数据。
• type_poll::change('id=?', $id, votes: ...) 通过模型更新记录：一个 where 子句，它的值，然后是命名列。使用 JSONDB 时，您总是通过静态模型方法进行写入。
• location('/poll') 进行重定向。POST、重定向、GET：自 2004 年以来安全刷新投票。

重新加载并点击 Phlo。页面重新加载，计数为 1，进度条跳到 100%。点击另一个选项，观察百分比重新分配。检查 data/poll.json 以查看磁盘上的投票情况。

5.3: Reading a payload instead

The id in the path is one style. The other is a request body, which you read through %payload. First enable the resource in data/app.json:

{
    "resources": [
        "DB/DB",
        "DB/model",
        "DB/JSONDB",
        "DB/JSON.result",
        "payload"
    ]
}

A payload-based version of the same route looks like this:

route POST poll vote @option {
	$id = (int)%payload->option
	if (!$option = type_poll::record(id: $id)) return false
	type_poll::change('id=?', $id, votes: $option->votes + 1)
	location('/poll')
}

@option validates the request body: the payload must contain exactly the key option, or the route does not match. Body keys are never bound as parameters; you read them via %payload->option. The matching form would be one form with <button name=option value="$option->id"> per choice.

Both styles are idiomatic. Keep the $id variant from 5.2 for this tutorial; it transitions cleanly into the async version.

5.4: What you have now

The build keeps itself current on every request; run the checks explicitly if you want the confirmation:

php www/app.php build::run
php www/app.php build::lint

Both settle at []. You have a complete, working poll: server-rendered, refresh-safe, zero JavaScript. Vote a few times, watch data/poll.json change, and notice the one thing that still feels 2004: the full page reload on every vote. That is the next chapter.

最近更新于 2026年8月23日