Flask Academy · 课时

渲染并提交表单

在模板中显示字段并处理提交

渲染并提交表单 是 CoddyKit 上的免费 Flask Academy 课时。这是第 2 节课，共 4 节。你可以在下方免费阅读本课时的完整内容 — 然后在浏览器中使用内置代码编辑器和全天候 AI 导师进行实践。这是 Flask Academy 学习路径的一部分，你的进度在网页和 CoddyKit 应用中同步。 Flask Academy 课程共包含 4 节课。

本课时的部分内容尚未翻译，以英文显示。

From Class to Page

A form class is useless until a user can see it. Now you will render those fields into HTML and accept the submission back. 🖋️

Pass the Form to the Template

Create the form in your view and hand it to render_template. The template gets a live object full of fields it can draw.

form = LoginForm()
return render_template('login.html', form=form)

Open the Form Tag

In Jinja, start with an HTML form tag set to method post. That tells the browser to send field values in the request body.

<form method="post">
  ...
</form>

Render the Hidden Tag

Call form.hidden_tag() first inside the form. It drops in the CSRF token your post will need to be accepted.

<form method="post">
  {{ form.hidden_tag() }}
</form>

Draw a Field

Each field renders itself when you call it. Use field.label for the text and the field itself for the input element.

{{ form.username.label }}
{{ form.username() }}

Pass HTML Attributes

Calling a field accepts keyword arguments that become HTML attributes. Add a class or placeholder right from the template.

{{ form.username(class="input", placeholder="Your name") }}

Render the Submit Button

The submit field draws the button. Calling form.submit() produces the input that posts the whole form.

{{ form.submit() }}

Allow POST in the Route

By default a route only answers GET. List methods so the same view can serve the page and receive the post.

@app.route('/login', methods=['GET', 'POST'])
def login():
    form = LoginForm()

Read Submitted Data

After a post, each field exposes a .data attribute holding the typed value, already coerced to the right Python type.

username = form.username.data
password = form.password.data

Auto-Populate on Reload

Flask-WTF fills fields from the request automatically. If you re-render after a post, the user's input stays in place.

form = LoginForm()  # picks up posted data on POST

One Template, Both Verbs

A single view handles GET and POST: build the form, process it on post, and re-render the same page otherwise.

form = LoginForm()
if form.is_submitted():
    pass  # handle data
return render_template('login.html', form=form)

Quick Check

What must you render inside the form to include the CSRF token?

Recap

You rendered fields with labels and attributes, added hidden_tag for CSRF, allowed POST, and read values from each field's .data. 🎉

常见问题解答

「渲染并提交表单」课时是免费的吗？

是的 — 「渲染并提交表单」的完整文本可在网页上免费阅读。要进行交互式练习（内置代码编辑器和全天候 AI 导师）并解锁 Flask Academy 课程的其余内容，请升级到 CoddyKit PRO。 Flask Academy 课程共包含 4 节课。

「渲染并提交表单」这节课中我会学到什么？

在模板中显示字段并处理提交你通过在浏览器中直接运行的动手代码来练习 Flask Academy，全天候 AI 导师会在你学习这节课的过程中回答你的问题。

学习 Flask Academy 需要有经验吗？

无需任何先前经验。CoddyKit 上的 Flask Academy 课程适合初学者到高级学习者，你可以从这里开始或从头开始，按照自己的节奏学习。这是第 2 节课，共 4 节。

「渲染并提交表单」课时需要多长时间？

大多数 CoddyKit 课程大约需要 5–10 分钟。每节课都很精短且互动，所以你能稳步进步，并在网页和应用中从离开的地方继续。

我能在这节 Flask Academy 课中编写并运行代码吗？

能。每节 Flask Academy 课都包含内置代码编辑器，你可以在浏览器中直接编写并运行真实代码，并获得即时 AI 反馈 — 无需本地设置。

此课程中的所有课时

← 返回 Flask Academy