```

## 定义 `File` 与 `Form` 参数

创建文件和表单参数的方式与 `Body` 和 `Query` 一样：

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

文件和表单字段作为表单数据上传与接收。

声明文件可以使用 `bytes` 或 `UploadFile` 。

/// warning | "警告"

可在一个*路径操作*中声明多个 `File` 与 `Form` 参数，但不能同时声明要接收 JSON 的 `Body` 字段。因为此时请求体的编码为 `multipart/form-data`，不是 `application/json`。

这不是 **FastAPI** 的问题，而是 HTTP 协议的规定。

///

## 小结

import pytest
from fastapi.testclient import TestClient

from docs_src.first_steps.tutorial001 import app

client = TestClient(app)


@pytest.mark.parametrize(
    "path,expected_status,expected_response",
    [
        ("/", 200, {"message": "Hello World"}),
        ("/nonexistent", 404, {"detail": "Not Found"}),
    ],
)
def test_get_path(path, expected_status, expected_response):
    response = client.get(path)

	//
	// Deprecated: Use UncompressedSize64 instead.
	UncompressedSize uint32

	// CompressedSize64 is the compressed size of the file in bytes.
	CompressedSize64 uint64

	// UncompressedSize64 is the uncompressed size of the file in bytes.
	UncompressedSize64 uint64

	Extra         []byte
	ExternalAttrs uint32 // Meaning depends on CreatorVersion
}

// FileInfo returns an fs.FileInfo for the [FileHeader].

from fastapi import FastAPI, File, UploadFile

app = FastAPI()


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


@app.post("/uploadfile/")
async def create_upload_file(file: UploadFile):

from fastapi import FastAPI, File, Form, UploadFile

app = FastAPI()


@app.post("/files/")
async def create_file(
    file: bytes = File(), fileb: UploadFile = File(), token: str = Form()
):
    return {
        "file_size": len(file),
        "token": token,
        "fileb_content_type": fileb.content_type,

          println("Executing test case $number/$count")
          startNanos.set(System.nanoTime())
        }

        override fun onMessage(
          webSocket: WebSocket,
          bytes: ByteString,
        ) {
          webSocket.send(bytes)
        }

        override fun onMessage(
          webSocket: WebSocket,
          text: String,
        ) {
          webSocket.send(text)
        }

   *   <li>The space character " " is converted into a plus sign "+".
   *   <li>All other characters are converted into one or more bytes using UTF-8 encoding and each
   *       byte is then represented by the 3-character string "%XY", where "XY" is the two-digit,
   *       uppercase, hexadecimal representation of the byte value.
   * </ul>
   *
   * <p>This escaper is suitable for escaping parameter names and values even when <a

	}
	return
}

// MarshalMsg implements msgp.Marshaler
func (z RMetricName) MarshalMsg(b []byte) (o []byte, err error) {
	o = msgp.Require(b, z.Msgsize())
	o = msgp.AppendString(o, string(z))
	return
}

// UnmarshalMsg implements msgp.Unmarshaler
func (z *RMetricName) UnmarshalMsg(bts []byte) (o []byte, err error) {
	{
		var zb0001 string
		zb0001, bts, err = msgp.ReadStringBytes(bts)

          // The cache cannot be written.
        }
      }
    }

    return response
  }

  /**
   * Returns a new source that writes bytes to [cacheRequest] as they are read by the source
   * consumer. This is careful to discard bytes left over when the stream is closed; otherwise we
   * may never exhaust the source stream and therefore not complete the cached response.
   */
  @Throws(IOException::class)

		}

		formValues.Set("Policy", base64.StdEncoding.EncodeToString([]byte(pp.String())))
		formValues.Set("Success_action_status", tt.SuccessActionStatus)
		policyBytes, err := base64.StdEncoding.DecodeString(base64.StdEncoding.EncodeToString([]byte(pp.String())))
		if err != nil {
			t.Fatal(err)
		}

		postPolicyForm, err := parsePostPolicyForm(bytes.NewReader(policyBytes))
		if err != nil {
			t.Fatal(err)
		}