///

檔案會以「表單資料」上傳。

如果你將路徑操作函式（path operation function）的參數型別宣告為 `bytes`，**FastAPI** 會替你讀取檔案，你會以 `bytes` 取得內容。

請注意，這表示整個內容會存放在記憶體中，適合小檔案。

但在許多情況下，使用 `UploadFile` 會更好。

## 使用 `UploadFile` 的檔案參數 { #file-parameters-with-uploadfile }

將檔案參數型別設為 `UploadFile`：

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

使用 `UploadFile` 相較於 `bytes` 有數個優點：

* 你不必在參數的預設值使用 `File()`。
* 它使用「spooled」檔案：

        // Then
        assertNotNull(result);
        assertFalse(result.isEmpty());
        // Should contain hex representation of first bytes
        assertTrue(result.startsWith("00010203"));
        assertEquals(64, result.length()); // 32 bytes * 2 chars per byte
    }

    @ParameterizedTest
    @ValueSource(ints = { 1, 16, 32, 64, 128, 256 })
    @DisplayName("Should handle various data sizes")

	}

	// Pre-allocate a buffer - 128 bytes is an arbitrary
	// heuristic value that seems like a good starting size.
	b := bytes.NewBuffer(make([]byte, 0, 128))
	if len(c) == 1 {
		for k, v := range c {
			b.WriteString(`{"`)
			escapeStringJSON(b, k)
			b.WriteString(`":"`)
			escapeStringJSON(b, v)
			b.WriteString(`"}`)
		}
		return b.Bytes(), nil
	}

	sortedKeys := make([]string, 0, len(c))

@app.get("/image/stream", response_class=PNGStreamingResponse)
async def stream_image() -> AsyncIterable[bytes]:
    with read_image() as image_file:
        for chunk in image_file:
            yield chunk


@app.get("/image/stream-no-async", response_class=PNGStreamingResponse)
def stream_image_no_async() -> Iterable[bytes]:
    with read_image() as image_file:
        for chunk in image_file:
            yield chunk

     * @param fid the file identifier
     * @param offset the file offset at which to write
     * @param remaining the number of bytes remaining to be written
     * @param b the data buffer containing bytes to write
     * @param off the offset in the buffer where data starts
     * @param len the number of bytes to write
     * @param andx the next command in the AndX chain, or null
     */

		return
	}

	if err = writer.Flush(); err != nil {
		fmt.Println("Flush Error:", err)
		return
	}

	fmt.Println("Bytes written:", n)
	fmt.Println("Buffer contents:", buf.String())
	// Output:
	// Bytes written: 41
	// Buffer contents: Hello, world!
	// This is a ReadFrom example.
}

// The simplest use of a Scanner, to read standard input as a set of lines.
func ExampleScanner_lines() {

	// Any value must end with a newline.
	// Not all clients send that.
	trailerRaw := valueBuffer.Bytes()
	if len(trailerRaw) > 0 && trailerRaw[len(trailerRaw)-1] != '\n' {
		valueBuffer.Write([]byte{'\n'})
	}
	sig = sig[len("x-amz-trailer-signature:"):]
	sig = bytes.TrimSpace(sig)
	cr.chunkSHA256Writer.Write(valueBuffer.Bytes())
	wantSig := cr.getTrailerChunkSignature()
	if !compareSignatureV4(string(sig), wantSig) {

        // Nonces should have proper size
        assertEquals(16, nonce1.length, "GCM nonce should be 16 bytes");
        assertEquals(16, nonce2.length, "GCM nonce should be 16 bytes");
        assertEquals(16, nonce3.length, "GCM nonce should be 16 bytes");

        // For GCM, last 4 bytes should contain incrementing counter
        ByteBuffer buffer1 = ByteBuffer.wrap(nonce1, 12, 4).order(java.nio.ByteOrder.LITTLE_ENDIAN);

        HashCode.fromBytes(digest.digest(input)), ALGORITHMS.get(algorithmName).hashBytes(input));
    for (int bytes = 4; bytes <= digest.getDigestLength(); bytes++) {
      assertEquals(
          HashCode.fromBytes(Arrays.copyOf(digest.digest(input), bytes)),
          new MessageDigestHashFunction(algorithmName, bytes, algorithmName).hashBytes(input));
    }
    int maxSize = digest.getDigestLength();
    assertThrows(

   *
   * @throws IllegalArgumentException if {@code bytes} has fewer than 4 elements
   */
  public static int fromByteArray(byte[] bytes) {
    checkArgument(bytes.length >= BYTES, "array too small: %s < %s", bytes.length, BYTES);
    return fromBytes(bytes[0], bytes[1], bytes[2], bytes[3]);
  }

  /**
   * Returns the {@code int} value whose byte representation is the given 4 bytes, in big-endian