Mas em situações reais, como implementações de segurança, você pode obter mais vantagens em usar as [Ferramentas de segurança integradas (o próximo capítulo)](../security/index.md){.internal-link target=_blank}.

///

## Erros das dependências e valores de retorno { #dependencies-errors-and-return-values }

Você pode utilizar as mesmas *funções* de dependências que você usaria normalmente.

import org.jspecify.annotations.NullUnmarked;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.JUnit4;

/**
 * Tests that the {@code ClassLoader} of {@link FinalizableReferenceQueue} can be unloaded. These
 * tests are separate from {@link FinalizableReferenceQueueTest} so that they can be excluded from
 * coverage runs, as the coverage system interferes with them.
 *
 * @author Eamonn McManus
 */
@AndroidIncompatible

///

### 尝试带有依赖项的 WebSockets

如果您的文件名为 `main.py`，请使用以下命令运行应用程序：

```console
$ uvicorn main:app --reload

<span style="color: green;">INFO</span>:     Uvicorn running on http://127.0.0.1:8000 (Press CTRL+C to quit)
```

在浏览器中打开 <a href="http://127.0.0.1:8000" class="external-link" target="_blank">http://127.0.0.1:8000</a>。

更多细节查看 <a href="https://www.starlette.dev/background/" class="external-link" target="_blank">Starlette's official docs for Background Tasks</a>.

## 告诫

如果您需要执行繁重的后台计算，并且不一定需要由同一进程运行（例如，您不需要共享内存、变量等），那么使用其他更大的工具（如 <a href="https://docs.celeryq.dev" class="external-link" target="_blank">Celery</a>）可能更好。

它们往往需要更复杂的配置，即消息/作业队列管理器，如RabbitMQ或Redis，但它们允许您在多个进程中运行后台任务，甚至是在多个服务器中。

  }

  /** Dispatches the given {@code event} to the given {@code subscribers}. */
  abstract void dispatch(Object event, Iterator<Subscriber> subscribers);

  /** Implementation of a {@link #perThreadDispatchQueue()} dispatcher. */
  private static final class PerThreadQueuedDispatcher extends Dispatcher {

    // This dispatcher matches the original dispatch behavior of EventBus.

import com.google.common.collect.testing.features.CollectionSize;
import java.lang.reflect.Method;
import java.util.Collection;
import org.junit.Ignore;

/**
 * Tests {@link java.util.Set#hashCode}.
 *
 * @author George van den Driessche
 */
@GwtCompatible
@Ignore("test runners must not instantiate and run this directly, only via suites we build")

/**
 * Helper class to manage {@link RequestTrace} for better error logging.
 *
 * @since 3.9.9
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */
@Deprecated(since = "4.0.0")
public final class RequestTraceHelper {

    /**
     * Method that creates some informational string based on passed in {@link RequestTrace}. The contents of request

Da **FastAPI** unter der Haube eigentlich **Starlette** ist, mit einer Ebene von mehreren Tools darüber, können Sie Starlettes <a href="https://www.starlette.dev/requests/" class="external-link" target="_blank">`Request`</a>-Objekt direkt verwenden, wenn Sie es benötigen.

İstek gövdesinde JSON verisi yerine form alanlarını karşılamanız gerketiğinde `Form` sınıfını kullanabilirsiniz.

/// info | Bilgi

Formları kullanmak için öncelikle <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a> paketini indirmeniz gerekmektedir.

Örneğin `pip install python-multipart`.

///

## `Form` Sınıfını Projenize Dahil Edin

`Form` sınıfını `fastapi`'den projenize dahil edin:

# 表单模型

您可以使用 **Pydantic 模型**在 FastAPI 中声明**表单字段**。

/// info

要使用表单，需预先安装 <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a> 。

确保您创建、激活一个[虚拟环境](../virtual-environments.md){.internal-link target=_blank}后再安装。

```console
$ pip install python-multipart
```

///

/// note

自 FastAPI 版本 `0.113.0` 起支持此功能。🤓

///

## 表单的 Pydantic 模型