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<p>JSON (JavaScript Object Notation) 是一种轻量级的数据交换格式，它基于 JavaScript 的一个子集。数据格式简洁和明了，具有易于读写的特性，常用于数据的存储和网络数据的交换。</p>
<h3 id="基本数据类型">基本数据类型<a aria-hidden="true" tabindex="-1" href="#基本数据类型" class="internal"> §</a></h3>
<p>JSON 支持以下数据类型：</p>
<ul>
<li>数字（整数或浮点数）</li>
<li>字符串（在双引号中）</li>
<li>布尔值（true 或 false）</li>
<li>数组（在方括号中）</li>
<li>对象（在大括号中）</li>
<li>null</li>
</ul>
<p>一个简单的 JSON 对象示例：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="json" data-theme="default"><code data-language="json" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">{</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">&quot;name&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;John&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">&quot;age&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">30</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">&quot;is_student&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">false</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">&quot;cars&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> [</span><span style="color:var(--shiki-token-string-expression);">&quot;Ford&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;BMW&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;Fiat&quot;</span><span style="color:var(--shiki-color-text);">]</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">&quot;pets&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">null</span></span>
<span data-line><span style="color:var(--shiki-color-text);">}</span></span></code></pre></div>
<h3 id="json-使用场景">JSON 使用场景<a aria-hidden="true" tabindex="-1" href="#json-使用场景" class="internal"> §</a></h3>
<p>JSON 的主要用途是在服务器和 web 应用之间传输数据。由于其简洁明了的特性，JSON 也被广泛用于配置文件、数据存储等场景。</p>
<h3 id="json-与-xml-的比较">JSON 与 XML 的比较<a aria-hidden="true" tabindex="-1" href="#json-与-xml-的比较" class="internal"> §</a></h3>
<p>JSON 和 XML 都是数据存储和传输的格式。与 XML 相比，JSON 更小、更快、更易解析。JSON 是语言无关的，它支持的数据结构在所有现代编程语言中都有对应的类型。而 XML 则更多地被用于文档的存储和传输。</p>
<h2 id="python-对-json-的支持">Python 对 JSON 的支持<a aria-hidden="true" tabindex="-1" href="#python-对-json-的支持" class="internal"> §</a></h2>
<p>Python 标准库中的 <code>json</code> 模块提供了 JSON 数据的编码和解码功能。它可以将 Python 对象转换为 JSON 字符串，也可以将 JSON 字符串解码为 Python 对象。</p>
<h3 id="json-模块的主要函数和对象">Json 模块的主要函数和对象<a aria-hidden="true" tabindex="-1" href="#json-模块的主要函数和对象" class="internal"> §</a></h3>
<p><code>json</code> 模块的主要函数包括：</p>
<ul>
<li><code>json.dumps()</code>：将 Python 对象编码成 JSON 字符串。</li>
<li><code>json.loads()</code>：将 JSON 字符串解码为 Python 对象。</li>
<li><code>json.dump()</code>：将 Python 对象编码成 JSON 字符串并写入文件。</li>
<li><code>json.load()</code>：读取文件中的 JSON 字符串并解码为 Python 对象。</li>
</ul>
<p><code>json</code> 模块的主要对象包括：</p>
<ul>
<li><code>json.JSONEncoder</code>：用于自定义编码。</li>
<li><code>json.JSONDecoder</code>：用于自定义解码。</li>
</ul>
<h2 id="json-编码">JSON 编码<a aria-hidden="true" tabindex="-1" href="#json-编码" class="internal"> §</a></h2>
<p>将 Python 对象转换为 JSON 格式。</p>
<h3 id="jsondumps-函数">json.dumps() 函数<a aria-hidden="true" tabindex="-1" href="#jsondumps-函数" class="internal"> §</a></h3>
<p><strong>将 Python 对象编码成 JSON 字符串。</strong></p>
<p><code>json.dumps()</code> 函数接受一个 Python 对象，并返回一个 JSON 格式的字符串。例如：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">person </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-punctuation);">{</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;name&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;John&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;age&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">30</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;is_student&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">False</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;cars&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> [</span><span style="color:var(--shiki-token-string-expression);">&quot;Ford&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;BMW&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;Fiat&quot;</span><span style="color:var(--shiki-color-text);">]</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;pets&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">None</span></span>
<span data-line><span style="color:var(--shiki-token-punctuation);">}</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">person_json </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">dumps</span><span style="color:var(--shiki-token-punctuation);">(person)</span></span>
<span data-line><span style="color:var(--shiki-token-function);">print</span><span style="color:var(--shiki-token-punctuation);">(person_json)</span></span></code></pre></div>
<h3 id="jsondump-函数">json.dump() 函数<a aria-hidden="true" tabindex="-1" href="#jsondump-函数" class="internal"> §</a></h3>
<p><strong>将 Python 对象编码成 JSON 字符串并写入文件。</strong></p>
<p><code>json.dump()</code> 函数与 <code>json.dumps()</code> 功能相同，但它不返回结果，而是直接将 JSON 字符串写入一个文件对象。例如：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">person </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-punctuation);">{</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;name&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;John&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;age&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">30</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;is_student&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">False</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;cars&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> [</span><span style="color:var(--shiki-token-string-expression);">&quot;Ford&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;BMW&quot;</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;Fiat&quot;</span><span style="color:var(--shiki-color-text);">]</span><span style="color:var(--shiki-token-punctuation);">,</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;pets&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">None</span></span>
<span data-line><span style="color:var(--shiki-token-punctuation);">}</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">with</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">open</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'person.json'</span><span style="color:var(--shiki-token-punctuation);">, </span><span style="color:var(--shiki-token-string-expression);">'w'</span><span style="color:var(--shiki-token-punctuation);">)</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">as</span><span style="color:var(--shiki-color-text);"> f</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">dump</span><span style="color:var(--shiki-token-punctuation);">(person, f)</span></span></code></pre></div>
<h2 id="json-解码">JSON 解码<a aria-hidden="true" tabindex="-1" href="#json-解码" class="internal"> §</a></h2>
<p>将 JSON 格式转换为 Python 对象。</p>
<h3 id="jsonloads-函数">json.loads() 函数<a aria-hidden="true" tabindex="-1" href="#jsonloads-函数" class="internal"> §</a></h3>
<p><strong>将 JSON 字符串解码为 Python 对象。</strong></p>
<p><code>json.loads()</code> 函数接受一个 JSON 格式的字符串，并返回一个 Python 对象。例如：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">person_json </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'{&quot;name&quot;: &quot;John&quot;, &quot;age&quot;: 30, &quot;is_student&quot;: false, &quot;cars&quot;: [&quot;Ford&quot;, &quot;BMW&quot;, &quot;Fiat&quot;], &quot;pets&quot;: null}'</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">person </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">loads</span><span style="color:var(--shiki-token-punctuation);">(person_json)</span></span>
<span data-line><span style="color:var(--shiki-token-function);">print</span><span style="color:var(--shiki-token-punctuation);">(person)</span></span></code></pre></div>
<h3 id="jsonload-函数">json.load() 函数<a aria-hidden="true" tabindex="-1" href="#jsonload-函数" class="internal"> §</a></h3>
<p><strong>读取文件中的 JSON 字符串并解码为 Python 对象。</strong></p>
<p><code>json.load()</code> 函数与 <code>json.loads()</code> 功能相同，但它读取一个文件对象中的 JSON 字符串，而不是直接解码字符串。例如：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">with</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">open</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'person.json'</span><span style="color:var(--shiki-token-punctuation);">, </span><span style="color:var(--shiki-token-string-expression);">'r'</span><span style="color:var(--shiki-token-punctuation);">)</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">as</span><span style="color:var(--shiki-color-text);"> f</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> person </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">load</span><span style="color:var(--shiki-token-punctuation);">(f)</span></span>
<span data-line><span style="color:var(--shiki-token-function);">print</span><span style="color:var(--shiki-token-punctuation);">(person)</span></span></code></pre></div>
<h2 id="自定义-json-编码和解码">自定义 JSON 编码和解码<a aria-hidden="true" tabindex="-1" href="#自定义-json-编码和解码" class="internal"> §</a></h2>
<h3 id="jsonjsonencoder-类进行自定义编码">json.JSONEncoder 类进行自定义编码<a aria-hidden="true" tabindex="-1" href="#jsonjsonencoder-类进行自定义编码" class="internal"> §</a></h3>
<p>如果你想对默认行为进行更多的控制，例如改变日期时间的格式，你可以自定义 <code>json.JSONEncoder</code> 类。例如：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">from</span><span style="color:var(--shiki-color-text);"> datetime </span><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> datetime</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">class</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">DateTimeEncoder</span><span style="color:var(--shiki-color-text);">(</span><span style="color:var(--shiki-token-function);">json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">JSONEncoder</span><span style="color:var(--shiki-color-text);">):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">def</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">default</span><span style="color:var(--shiki-color-text);">(</span><span style="color:var(--shiki-token-parameter);">self</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-parameter);">o</span><span style="color:var(--shiki-color-text);">):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">if</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">isinstance</span><span style="color:var(--shiki-token-punctuation);">(o, datetime):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">return</span><span style="color:var(--shiki-color-text);"> o</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">isoformat</span><span style="color:var(--shiki-token-punctuation);">()</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">return</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">super</span><span style="color:var(--shiki-token-punctuation);">().</span><span style="color:var(--shiki-token-function);">default</span><span style="color:var(--shiki-token-punctuation);">(o)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">now </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> datetime</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">now</span><span style="color:var(--shiki-token-punctuation);">()</span></span>
<span data-line><span style="color:var(--shiki-color-text);">json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">dumps</span><span style="color:var(--shiki-token-punctuation);">(now, cls</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">DateTimeEncoder)</span></span></code></pre></div>
<h3 id="jsonjsondecoder-类进行自定义解码">json.JSONDecoder 类进行自定义解码<a aria-hidden="true" tabindex="-1" href="#jsonjsondecoder-类进行自定义解码" class="internal"> §</a></h3>
<p>同样，你可以自定义 <code>json.JSONDecoder</code> 类来对 JSON 字符串进行特殊的解码。例如，你可以解析特定的日期时间格式：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">from</span><span style="color:var(--shiki-color-text);"> datetime </span><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> datetime</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">class</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">DateTimeDecoder</span><span style="color:var(--shiki-color-text);">(</span><span style="color:var(--shiki-token-function);">json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">JSONDecoder</span><span style="color:var(--shiki-color-text);">):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">def</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">object_hook</span><span style="color:var(--shiki-color-text);">(</span><span style="color:var(--shiki-token-parameter);">self</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-parameter);">dict_</span><span style="color:var(--shiki-color-text);">):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">for</span><span style="color:var(--shiki-color-text);"> key</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> value </span><span style="color:var(--shiki-token-keyword);">in</span><span style="color:var(--shiki-color-text);"> dict_</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">items</span><span style="color:var(--shiki-token-punctuation);">():</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">try</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> dict_</span><span style="color:var(--shiki-token-punctuation);">[</span><span style="color:var(--shiki-color-text);">key</span><span style="color:var(--shiki-token-punctuation);">]</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> datetime</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">strptime</span><span style="color:var(--shiki-token-punctuation);">(value, </span><span style="color:var(--shiki-token-string-expression);">&quot;%Y-%m-</span><span style="color:var(--shiki-token-constant);">%d</span><span style="color:var(--shiki-token-string-expression);">T%H:%M:%S&quot;</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">except</span><span style="color:var(--shiki-color-text);"> (</span><span style="color:var(--shiki-token-constant);">TypeError</span><span style="color:var(--shiki-token-punctuation);">,</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">ValueError</span><span style="color:var(--shiki-color-text);">)</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">pass</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">return</span><span style="color:var(--shiki-color-text);"> dict_</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">json_string </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'{&quot;name&quot;: &quot;John&quot;, &quot;birthday&quot;: &quot;2000-01-01T00:00:00&quot;}'</span></span>
<span data-line><span style="color:var(--shiki-color-text);">json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">loads</span><span style="color:var(--shiki-token-punctuation);">(json_string, cls</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">DateTimeDecoder)</span></span></code></pre></div>
<h2 id="处理复杂的-json-数据">处理复杂的 JSON 数据<a aria-hidden="true" tabindex="-1" href="#处理复杂的-json-数据" class="internal"> §</a></h2>
<h3 id="使用嵌套的数据结构处理复杂的-json-数据">使用嵌套的数据结构处理复杂的 JSON 数据<a aria-hidden="true" tabindex="-1" href="#使用嵌套的数据结构处理复杂的-json-数据" class="internal"> §</a></h3>
<p>JSON 可以表示复杂的嵌套数据结构，包括嵌套的对象和数组。你可以使用 Python 的字典、列表、元组等数据结构来处理这些复杂的 JSON 数据。</p>
<h3 id="如何处理-json-数据中的日期和时间">如何处理 JSON 数据中的日期和时间<a aria-hidden="true" tabindex="-1" href="#如何处理-json-数据中的日期和时间" class="internal"> §</a></h3>
<p>JSON 格式本身并不支持日期和时间类型，一般以字符串形式表示。你可以在编码和解码时使用自定义的 <code>json.JSONEncoder</code> 和 <code>json.JSONDecoder</code> 类来处理日期和时间。</p>
<h3 id="如何处理-json-数据中的自定义对象">如何处理 JSON 数据中的自定义对象<a aria-hidden="true" tabindex="-1" href="#如何处理-json-数据中的自定义对象" class="internal"> §</a></h3>
<p>你可以重写 <code>json.JSONEncoder</code> 的 <code>default()</code> 方法和 <code>json.JSONDecoder</code> 的 <code>object_hook()</code> 方法来处理自定义对象。</p>
<h2 id="错误和异常处理">错误和异常处理<a aria-hidden="true" tabindex="-1" href="#错误和异常处理" class="internal"> §</a></h2>
<p>在使用 <code>json</code> 模块时，你可能会遇到以下几种错误和异常：</p>
<ul>
<li><code>json.JSONDecodeError</code>：在解码 JSON 数据时发生的错误。</li>
<li><code>TypeError</code>：当你试图将不可序列化的对象（如函数）编码为 JSON 时，<code>json.dumps()</code> 和 <code>json.dump()</code> 会抛出这个错误。</li>
</ul>
<h3 id="处理错误和异常">处理错误和异常<a aria-hidden="true" tabindex="-1" href="#处理错误和异常" class="internal"> §</a></h3>
<p>你可以使用 Python 的异常处理机制来处理这些错误和异常，例如：</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="python" data-theme="default"><code data-language="python" data-theme="default"><span data-line><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> json</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">try</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> person_json </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'{&quot;name&quot;: &quot;John&quot;, &quot;age&quot;: 30, &quot;is_student&quot;: false, &quot;cars&quot;: [&quot;Ford&quot;, &quot;BMW&quot;, &quot;Fiat&quot;], &quot;pets&quot;: null,'</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> person </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">loads</span><span style="color:var(--shiki-token-punctuation);">(person_json)</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">except</span><span style="color:var(--shiki-color-text);"> json</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-color-text);">JSONDecodeError </span><span style="color:var(--shiki-token-keyword);">as</span><span style="color:var(--shiki-color-text);"> e</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">print</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-keyword);">f</span><span style="color:var(--shiki-token-string-expression);">&quot;Invalid JSON: </span><span style="color:var(--shiki-token-constant);">{</span><span style="color:var(--shiki-token-punctuation);">e</span><span style="color:var(--shiki-token-constant);">}</span><span style="color:var(--shiki-token-string-expression);">&quot;</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">except</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">TypeError</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-keyword);">as</span><span style="color:var(--shiki-color-text);"> e</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">print</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-keyword);">f</span><span style="color:var(--shiki-token-string-expression);">&quot;Type Error: </span><span style="color:var(--shiki-token-constant);">{</span><span style="color:var(--shiki-token-punctuation);">e</span><span style="color:var(--shiki-token-constant);">}</span><span style="color:var(--shiki-token-string-expression);">&quot;</span><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div></article></div><div class="right sidebar"><div class="graph "><h3>Graph View</h3><div class="graph-outer"><div id="graph-container" data-cfg="{&quot;drag&quot;:true,&quot;zoom&quot;:true,&quot;depth&quot;:1,&quot;scale&quot;:1.1,&quot;repelForce&quot;:0.5,&quot;centerForce&quot;:0.3,&quot;linkDistance&quot;:30,&quot;fontSize&quot;:0.6,&quot;opacityScale&quot;:1,&quot;showTags&quot;:true,&quot;removeTags&quot;:[]}"></div><svg version="1.1" id="global-graph-icon" xmlns="http://www.w3.org/2000/svg" xmlnsXlink="http://www.w3.org/1999/xlink" x="0px" y="0px" viewBox="0 0 55 55" fill="currentColor" xmlSpace="preserve"><path d="M49,0c-3.309,0-6,2.691-6,6c0,1.035,0.263,2.009,0.726,2.86l-9.829,9.829C32.542,17.634,30.846,17,29,17
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s-2-0.897-2-2s0.897-2,2-2S47,39.897,47,41z M49,10c-2.206,0-4-1.794-4-4s1.794-4,4-4s4,1.794,4,4S51.206,10,49,10z"></path></svg></div><div id="global-graph-outer"><div id="global-graph-container" data-cfg="{&quot;drag&quot;:true,&quot;zoom&quot;:true,&quot;depth&quot;:-1,&quot;scale&quot;:0.9,&quot;repelForce&quot;:0.5,&quot;centerForce&quot;:0.3,&quot;linkDistance&quot;:30,&quot;fontSize&quot;:0.6,&quot;opacityScale&quot;:1,&quot;showTags&quot;:true,&quot;removeTags&quot;:[]}"></div></div></div><div class="toc desktop-only"><button type="button" id="toc" class><h3>Table of Contents</h3><svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="fold"><polyline points="6 9 12 15 18 9"></polyline></svg></button><div id="toc-content"><ul class="overflow"><li class="depth-0"><a href="#json-是什么" data-for="json-是什么">JSON 是什么</a></li><li class="depth-1"><a href="#基本数据类型" data-for="基本数据类型">基本数据类型</a></li><li class="depth-1"><a href="#json-使用场景" data-for="json-使用场景">JSON 使用场景</a></li><li class="depth-1"><a href="#json-与-xml-的比较" data-for="json-与-xml-的比较">JSON 与 XML 的比较</a></li><li class="depth-0"><a href="#python-对-json-的支持" data-for="python-对-json-的支持">Python 对 JSON 的支持</a></li><li class="depth-1"><a href="#json-模块的主要函数和对象" data-for="json-模块的主要函数和对象">Json 模块的主要函数和对象</a></li><li class="depth-0"><a href="#json-编码" data-for="json-编码">JSON 编码</a></li><li class="depth-1"><a href="#jsondumps-函数" data-for="jsondumps-函数">json.dumps() 函数</a></li><li class="depth-1"><a href="#jsondump-函数" data-for="jsondump-函数">json.dump() 函数</a></li><li class="depth-0"><a href="#json-解码" data-for="json-解码">JSON 解码</a></li><li class="depth-1"><a href="#jsonloads-函数" data-for="jsonloads-函数">json.loads() 函数</a></li><li class="depth-1"><a href="#jsonload-函数" data-for="jsonload-函数">json.load() 函数</a></li><li class="depth-0"><a href="#自定义-json-编码和解码" data-for="自定义-json-编码和解码">自定义 JSON 编码和解码</a></li><li class="depth-1"><a href="#jsonjsonencoder-类进行自定义编码" data-for="jsonjsonencoder-类进行自定义编码">json.JSONEncoder 类进行自定义编码</a></li><li class="depth-1"><a href="#jsonjsondecoder-类进行自定义解码" data-for="jsonjsondecoder-类进行自定义解码">json.JSONDecoder 类进行自定义解码</a></li><li class="depth-0"><a href="#处理复杂的-json-数据" data-for="处理复杂的-json-数据">处理复杂的 JSON 数据</a></li><li class="depth-1"><a href="#使用嵌套的数据结构处理复杂的-json-数据" data-for="使用嵌套的数据结构处理复杂的-json-数据">使用嵌套的数据结构处理复杂的 JSON 数据</a></li><li class="depth-1"><a href="#如何处理-json-数据中的日期和时间" data-for="如何处理-json-数据中的日期和时间">如何处理 JSON 数据中的日期和时间</a></li><li class="depth-1"><a href="#如何处理-json-数据中的自定义对象" data-for="如何处理-json-数据中的自定义对象">如何处理 JSON 数据中的自定义对象</a></li><li class="depth-0"><a href="#错误和异常处理" data-for="错误和异常处理">错误和异常处理</a></li><li class="depth-1"><a href="#处理错误和异常" data-for="处理错误和异常">处理错误和异常</a></li></ul></div></div><div class="backlinks "><h3>Backlinks</h3><ul class="overflow"><li><a href="../../../../../Tech/programming-language/Python/进阶/文件和IO操作" class="internal">文件和IO操作</a></li></ul></div><div class="explorer mobile-only"><button type="button" id="explorer" data-behavior="collapse" data-collapsed="collapsed" data-savestate="true" data-tree="[{&quot;path&quot;:&quot;Basics&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quo
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