}

    int type, length;

    /**
     * Writes the packet to the specified byte array in wire format.
     *
     * @param dst the destination byte array to write to
     * @param dstIndex the starting index in the destination array
     * @return the number of bytes written
     */
    public int writeWireFormat(final byte[] dst, final int dstIndex) {
        length = writeTrailerWireFormat(dst, dstIndex + HEADER_LENGTH);

在*路径操作装饰器*中使用 `dependencies` 参数，可以确保在执行依赖项的同时，避免编辑器显示错误提示。

使用路径装饰器依赖项还可以避免开发新人误会代码中包含无用的未使用参数。

///

/// info | 说明

本例中，使用的是自定义响应头 `X-Key` 和 `X-Token`。

但实际开发中，尤其是在实现安全措施时，最好使用 FastAPI 内置的[安全工具](../security/index.md){.internal-link target=_blank}（详见下一章）。

///

## 依赖项错误和返回值

路径装饰器依赖项也可以使用普通的依赖项*函数*。

### 依赖项的需求项

路径装饰器依赖项可以声明请求的需求项（比如响应头）或其他子依赖项：

{* ../../docs_src/dependencies/tutorial006.py hl[6,11] *}

    ImmutableList<String> list = multiset.asList();
    assertEquals(ImmutableList.of("a", "a", "b", "b", "b"), list);
    SerializableTester.reserializeAndAssert(list);
    assertEquals(2, list.indexOf("b"));
    assertEquals(4, list.lastIndexOf("b"));
  }

  private static class IntegerDiv10 implements Comparable<IntegerDiv10> {
    final int value;

    IntegerDiv10(int value) {

        } catch (final IOException e) {
            throw new DictionaryException("Failed to parse " + path, e);
        }
    }

    private String unescape(final String s) {
        if (s.indexOf('\\') >= 0) {
            final StringBuilder sb = new StringBuilder();
            for (int i = 0; i < s.length(); i++) {
                final char ch = s.charAt(i);
                if (ch == '\\' && i < s.length() - 1) {

    /**
     * Constructs KerberosEncData from encrypted token bytes.
     *
     * @param token the encrypted Kerberos token
     * @param keys map of encryption keys indexed by key type
     * @throws PACDecodingException if decoding fails
     */
    public KerberosEncData(byte[] token, Map<Integer, KerberosKey> keys) throws PACDecodingException {

   * they're defined above -- including logic to add and subtract 1 to map between the values stored
   * in the predecessor/successor arrays and the indexes in the elements array that they identify.
   */

   * they're defined above -- including logic to add and subtract 1 to map between the values stored
   * in the predecessor/successor arrays and the indexes in the elements array that they identify.
   */

///

## Anwendungsfälle { #use-cases }

Einige Anwendungsfälle sind:

* Konvertieren von Nicht-JSON-Requestbodys nach JSON (z. B. <a href="https://msgpack.org/index.html" class="external-link" target="_blank">`msgpack`</a>).
* Dekomprimierung gzip-komprimierter Requestbodys.
* Automatisches Loggen aller Requestbodys.

			ID uint
		}
		Level3 struct {
			ID       uint
			Level4ID sql.NullInt64 `sql:"index"`
			Level4   *Level4
		}
		Level2 struct {
			ID      uint
			Level3s []*Level3 `gorm:"many2many:level2_level3s"`
		}
		Level1 struct {
			ID       uint
			Level2ID sql.NullInt64 `sql:"index"`
			Level2   *Level2
		}
	)

us: var(--bs-border-radius-pill) !important;\n}\n\n.visible {\n  visibility: visible !important;\n}\n\n.invisible {\n  visibility: hidden !important;\n}\n\n.z-n1 {\n  z-index: -1 !important;\n}\n\n.z-0 {\n  z-index: 0 !important;\n}\n\n.z-1 {\n  z-index: 1 !important;\n}\n\n.z-2 {\n  z-index: 2 !important;\n}\n\n.z-3 {\n  z-index: 3 !important;\n}\n\n@media (min-width: 576px) {\n  .float-sm-start {\n    float: left !important;\n  }\n  .float-sm-end {\n    float: right !important;\n  }\n  .float-sm-none...