from fastapi import Depends, FastAPI

app = FastAPI()


async def common_parameters(q: str | None = None, skip: int = 0, limit: int = 100):
    return {"q": q, "skip": skip, "limit": limit}


@app.get("/items/")
async def read_items(commons: dict = Depends(common_parameters)):
    return commons


@app.get("/users/")
async def read_users(commons: dict = Depends(common_parameters)):

from typing import Annotated

from fastapi import Depends, FastAPI

app = FastAPI()


async def common_parameters(q: str | None = None, skip: int = 0, limit: int = 100):
    return {"q": q, "skip": skip, "limit": limit}


@app.get("/items/")
async def read_items(commons: Annotated[dict, Depends(common_parameters)]):
    return commons


@app.get("/users/")
async def read_users(commons: Annotated[dict, Depends(common_parameters)]):

func NewQueueStore[I any](directory string, limit uint64, ext string) *QueueStore[I] {
	if limit == 0 {
		limit = defaultLimit
	}

	if ext == "" {
		ext = defaultExt
	}

	return &QueueStore[I]{
		directory:  directory,
		entryLimit: limit,
		fileExt:    ext,
		entries:    make(map[string]int64, limit),
	}
}

// Open - Creates the directory if not present.

Zum Beispiel sind in der URL:

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

... die Query-Parameter:

* `skip`: mit dem Wert `0`
* `limit`: mit dem Wert `10`

Da sie Teil der URL sind, sind sie „naturgemäß“ Strings.

                                        .collect(Collectors.toList()))
                                .build());
                    }

                    @Override
                    public Collection<Link> links() {
                        return Collections.emptyList();
                    }

                    @Override
                    public List<Phase> phases() {
                        return Collections.emptyList();

     *
     * @param expectTag the expected tag number
     * @param limit the maximum length limit
     * @param in the ASN.1 input stream
     * @return coded bytes of the tagged object
     * @throws IOException if reading fails or tag mismatch
     */
    public static byte[] readUnparsedTagged(final int expectTag, final int limit, final ASN1InputStream in) throws IOException {
        final int ftag = in.read();

    session.refresh(hero)
    return hero


@app.get("/heroes/")
def read_heroes(
    session: Session = Depends(get_session),
    offset: int = 0,
    limit: int = Query(default=100, le=100),
) -> list[Hero]:
    heroes = session.exec(select(Hero).offset(offset).limit(limit)).all()
    return heroes


@app.get("/heroes/{hero_id}")
def read_hero(hero_id: int, session: Session = Depends(get_session)) -> Hero:

                            "required": False,
                            "schema": {
                                "title": "Limit",
                                "type": "integer",
                                "default": 10,
                            },
                            "name": "limit",
                            "in": "query",
                        },
                    ],
                    "responses": {

                .toList();
    }

    @Override
    @Nonnull
    public List<Profile> getDeclaredActiveProfiles() {
        return project.getActiveProfiles().stream()
                .map(org.apache.maven.model.Profile::getDelegate)
                .toList();
    }

    @Override
    @Nonnull
    public List<Profile> getEffectiveActiveProfiles() {

* API 文档

## 默认值

查询参数不是路径的固定内容，它是可选的，还支持默认值。

上例用 `skip=0` 和 `limit=10` 设定默认值。

访问 URL：

```
http://127.0.0.1:8000/items/
```

与访问以下地址相同：

```
http://127.0.0.1:8000/items/?skip=0&limit=10
```

但如果访问：

```
http://127.0.0.1:8000/items/?skip=20
```

查询参数的值就是：

* `skip=20`：在 URL 中设定的值
* `limit=10`：使用默认值

## 可选参数

同理，把默认值设为 `None` 即可声明**可选的**查询参数：