HTML-Formulare (`<form></form>`) senden die Daten in einer „speziellen“ Kodierung zum Server, welche sich von JSON unterscheidet.

**FastAPI** stellt sicher, dass diese Daten korrekt ausgelesen werden, statt JSON zu erwarten.

/// note | "Technische Details"

Daten aus Formularen werden normalerweise mit dem <abbr title='Media type – Medientyp, Typ des Mediums'>„media type“</abbr> `application/x-www-form-urlencoded` kodiert.

## メタデータの宣言

パラメータは`Query`と同じものを宣言することができます。

例えば、パスパラメータ`item_id`に対して`title`のメタデータを宣言するには以下のようにします:

```Python hl_lines="8"
{!../../docs_src/path_params_numeric_validations/tutorial001.py!}
```

/// note | "備考"

パスの一部でなければならないので、パスパラメータは常に必須です。

そのため、`...`を使用して必須と示す必要があります。

それでも、`None`で宣言しても、デフォルト値を設定しても、何の影響もなく、常に必要とされていることに変わりはありません。

///

## 必要に応じてパラメータを並び替える

クエリパラメータ`q`を必須の`str`として宣言したいとしましょう。

////

//// tab | 🐍 3️⃣.1️⃣0️⃣ & 🔛

```Python hl_lines="9-12"
{!> ../../docs_src/body_fields/tutorial001_py310.py!}
```

////

`Field` 👷 🎏 🌌 `Query`, `Path` & `Body`, ⚫️ ✔️ 🌐 🎏 🔢, ♒️.

/// note | "📡 ℹ"

🤙, `Query`, `Path` & 🎏 👆 🔜 👀 ⏭ ✍ 🎚 🏿 ⚠ `Param` 🎓, ❔ ⚫️ 🏿 Pydantic `FieldInfo` 🎓.

 & Pydantic `Field` 📨 👐 `FieldInfo` 👍.

🔰, 👆 💪 💚 ❎ ⚫️ ⏮️ 🌐 📦 🔗 & ⚒:

<div class="termy">

```console
$ pip install "fastapi[all]"

---> 100%
```

</div>

...👈 🔌 `uvicorn`, 👈 👆 💪 ⚙️ 💽 👈 🏃 👆 📟.

/// note

👆 💪 ❎ ⚫️ 🍕 🍕.

👉 ⚫️❔ 👆 🔜 🎲 🕐 👆 💚 🛠️ 👆 🈸 🏭:

```
pip install "fastapi[standard]"
```

❎ `uvicorn` 👷 💽:

```
pip install "uvicorn[standard]"
```

import typing

from fastapi import Body, FastAPI
from fastapi.testclient import TestClient
from pydantic import BaseModel

app = FastAPI()

media_type = "application/vnd.api+json"


# NOTE: These are not valid JSON:API resources
# but they are fine for testing requestBody with custom media_type
class Product(BaseModel):
    name: str
    price: float


class Shop(BaseModel):
    name: str


@app.post("/products")

{!> ../../docs_src/header_params/tutorial001_py310.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="9"
{!> ../../docs_src/header_params/tutorial001.py!}
```

////

/// note | "Detalhes Técnicos"

`Header` é uma classe "irmã" de `Path`, `Query` e `Cookie`. Ela também herda da mesma classe em comum `Param`.

The way HTML forms (`<form></form>`) sends the data to the server normally uses a "special" encoding for that data, it's different from JSON.

**FastAPI** will make sure to read that data from the right place instead of JSON.

/// note | "Technical Details"

Data from forms is normally encoded using the "media type" `application/x-www-form-urlencoded`.

### GNU/Linux and macOS

```sh
docker-compose pull
docker-compose up
```

   * PackageSanityTests. (The test would run on the JVM, too, if not for the suppression below, and
   * that would be a problem because it violates small-test rules. Note that we strip the
   * suppression externally, but it's OK because we don't enforce test-size rules there.)
   *
   * We'd just use PackageSanityTests directly, saving us from needing this separate type, but we're

          sb.append(iterator.next());
        }
      }
      dummy ^= sb.toString().length();
    }
    return dummy;
  }

  /**
   * Only appends delimiter if the accumulated string is non-empty. Note: this isn't a candidate
   * implementation for Joiner since it fails on leading empty components.
   */
  @Benchmark
  int stringBuilderIsEmpty(int reps) {
    int dummy = 0;
    for (int i = 0; i < reps; i++) {