# `UploadFile` class

You can define *path operation function* parameters to be of the type `UploadFile` to receive files from the request.

You can import it directly from `fastapi`:

```python
from fastapi import UploadFile
```

::: fastapi.UploadFile
    options:
        members:
            - file
            - filename
            - size
            - headers
            - content_type
            - read

from starlette.datastructures import UploadFile as StarletteUploadFile


class UploadFile(StarletteUploadFile):
    """
    A file uploaded in a request.

    Define it as a *path operation function* (or dependency) parameter.

    If you are using a regular `def` function, you can use the `upload_file.file`
    attribute to access the raw standard Python file (blocking, not async), useful and

String buildNumber = System.getenv('BUILD_NUMBER')

if (buildNumber) {
  File uploadFile = file("build/${buildNumber}.tar.bz2")
  project.gradle.buildFinished { result ->
    println "build complete, generating: $uploadFile"
    if (uploadFile.exists()) {
      project.delete(uploadFile)
    }

    try {
      ant.tar(destfile: uploadFile, compression: "bzip2", longfile: "gnu") {
        fileset(dir: projectDir) {

Aber es gibt viele Fälle, in denen Sie davon profitieren, `UploadFile` zu verwenden.

## Datei-Parameter mit `UploadFile` { #file-parameters-with-uploadfile }

Definieren Sie einen Datei-Parameter mit dem Typ `UploadFile`:

{* ../../docs_src/request_files/tutorial001_an_py310.py hl[14] *}

`UploadFile` zu verwenden, hat mehrere Vorzüge gegenüber `bytes`:

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: bytes = File(description="A file read as bytes")):
    return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(
    file: UploadFile = File(description="A file read as UploadFile"),
):

from typing import Annotated

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(file: Annotated[bytes | None, File()] = None):
    if not file:
        return {"message": "No file sent"}
    else:
        return {"file_size": len(file)}


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile | None = None):
    if not file:

Mais dans plusieurs cas, vous pourriez bénéficier de l'utilisation d'`UploadFile`.

## Paramètres de fichier avec `UploadFile` { #file-parameters-with-uploadfile }

Définissez un paramètre de fichier de type `UploadFile` :

{* ../../docs_src/request_files/tutorial001_an_py310.py hl[14] *}

Utiliser `UploadFile` présente plusieurs avantages par rapport à `bytes` :

Pero hay varios casos en los que podrías beneficiarte de usar `UploadFile`.

## Parámetros de Archivo con `UploadFile` { #file-parameters-with-uploadfile }

Define un parámetro de archivo con un tipo de `UploadFile`:

{* ../../docs_src/request_files/tutorial001_an_py310.py hl[14] *}

Usar `UploadFile` tiene varias ventajas sobre `bytes`:

如果把*路径操作函数*参数的类型声明为 `bytes`，**FastAPI** 会为你读取文件，并以 `bytes` 的形式接收其内容。

请注意，这意味着整个内容会存储在内存中，适用于小型文件。

不过，在很多情况下，使用 `UploadFile` 会更有优势。

## 含 `UploadFile` 的文件参数 { #file-parameters-with-uploadfile }

将文件参数的类型声明为 `UploadFile`：

{* ../../docs_src/request_files/tutorial001_an_py310.py hl[14] *}

与 `bytes` 相比，使用 `UploadFile` 有多项优势：

* 无需在参数的默认值中使用 `File()`。
* 它使用“spooled”文件：
    * 文件会先存储在内存中，直到达到最大上限，超过该上限后会写入磁盘。

But there are several cases in which you might benefit from using `UploadFile`.

## File Parameters with `UploadFile` { #file-parameters-with-uploadfile }

Define a file parameter with a type of `UploadFile`:

{* ../../docs_src/request_files/tutorial001_an_py310.py hl[14] *}

Using `UploadFile` has several advantages over `bytes`:

* You don't have to use `File()` in the default value of the parameter.