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<p>Jinja2 的设计理念源自 Django 模板引擎,但在易用性、扩展性和性能上做出了大幅提升。</p>
<h2 id="安装">安装<a aria-hidden="true" tabindex="-1" href="#安装" class="internal"> §</a></h2>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="shell" data-theme="default"><code data-language="shell" data-theme="default"><span data-line><span style="color:var(--shiki-token-function);">pip</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string);">install</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string);">jinja2</span></span></code></pre></div>
<p>Jinja2 没有复杂的依赖 ,安装后可以直接导入和使用。</p>
<h2 id="核心功能">核心功能<a aria-hidden="true" tabindex="-1" href="#核心功能" class="internal"> §</a></h2>
<h3 id="创建模板环境">创建模板环境<a aria-hidden="true" tabindex="-1" href="#创建模板环境" class="internal"> §</a></h3>
<p><strong>使用 Jinja2 时 ,第一步是创建一个模板环境。<strong>模板环境包含了模板的各种配置选项 ,如全局函数、过滤器、测试等。通常</strong>一个应用只需要创建一个环境。</strong></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);">from</span><span style="color:var(--shiki-color-text);"> jinja2 </span><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> Environment PackageLoader select_autoescape</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">env </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">Environment</span><span style="color:var(--shiki-token-punctuation);">(</span></span>
<span data-line><span style="color:var(--shiki-token-punctuation);"> loader</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-function);">PackageLoader</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'yourapplication'</span><span style="color:var(--shiki-token-punctuation);"> </span><span style="color:var(--shiki-token-string-expression);">'templates'</span><span style="color:var(--shiki-token-punctuation);">) </span></span>
<span data-line><span style="color:var(--shiki-token-punctuation);"> autoescape</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-function);">select_autoescape</span><span style="color:var(--shiki-token-punctuation);">([</span><span style="color:var(--shiki-token-string-expression);">'html'</span><span style="color:var(--shiki-token-punctuation);"> </span><span style="color:var(--shiki-token-string-expression);">'xml'</span><span style="color:var(--shiki-token-punctuation);">])</span></span>
<span data-line><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div>
<p>这里我们使用 <code>PackageLoader</code> 加载 <code>app/templates</code> 目录下的模板 ,并开启了自动转义 HTML 和 XML 的功能 ,以防范 XSS 攻击。<code>trim_blocks</code> 选项可以去除模板代码前后的空行。</p>
<h3 id="定义模板">定义模板<a aria-hidden="true" tabindex="-1" href="#定义模板" class="internal"> §</a></h3>
<p>Jinja2 使用类 HTML 语法的模板文件 ,其中嵌入了一些特殊的语法来完成变量替换、逻辑控制等功能。例如:</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="jinja2" data-theme="default"><code data-language="jinja2" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">&lt;!DOCTYPE html></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;html></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;head></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;title>{{ title }}&lt;/title></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/head></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;body></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;ul></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% for item in items %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;li>{{ loop.index }}: {{ item }}&lt;/li></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% endfor %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/ul></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/body></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/html></span></span></code></pre></div>
<p>这个模板实现了一个简单的动态列表渲染 使用了变量、for 循环等模板语法。</p>
<h3 id="渲染模板">渲染模板<a aria-hidden="true" tabindex="-1" href="#渲染模板" class="internal"> §</a></h3>
<p>加载一个模板并渲染只需要简单的两步:</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-color-text);">template </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> env</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">get_template</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'index.html'</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-color-text);">content </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> template</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">render</span><span style="color:var(--shiki-token-punctuation);">(title</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-string-expression);">'Home'</span><span style="color:var(--shiki-token-punctuation);"> items</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">[</span><span style="color:var(--shiki-token-string-expression);">'A'</span><span style="color:var(--shiki-token-punctuation);"> </span><span style="color:var(--shiki-token-string-expression);">'B'</span><span style="color:var(--shiki-token-punctuation);"> </span><span style="color:var(--shiki-token-string-expression);">'C'</span><span style="color:var(--shiki-token-punctuation);">])</span></span></code></pre></div>
<p>这样就可以通过一个字典对象传入变量 ,生成最后的文本结果。</p>
<p>Jinja2 也支持模板继承 ,一个基础模板可以被多个页面模板扩展:</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="jinja2" data-theme="default"><code data-language="jinja2" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">{# base.html #}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;!DOCTYPE html></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;html></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;body></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% block content %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% endblock %} </span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/body></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/html></span></span>
<span data-line><span style="color:var(--shiki-color-text);"></span></span>
<span data-line><span style="color:var(--shiki-color-text);"></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{# index.html #}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% extends &quot;base.html&quot; %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% block content %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;p>This is Index Page.&lt;/p> </span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endblock %}</span></span></code></pre></div>
<h2 id="实践使用">实践使用<a aria-hidden="true" tabindex="-1" href="#实践使用" class="internal"> §</a></h2>
<h3 id="帖子应用">帖子应用<a aria-hidden="true" tabindex="-1" href="#帖子应用" class="internal"> §</a></h3>
<p>以下是一个使用 FlaskPython Web 框架)和 Jinja 的简单帖子列表应用,这个应用将允许用户查看帖子列表,并点击一个帖子以查看其详细内容。</p>
<p>前端部分将使用 Jinja 来生成 HTML后端部分将使用 Flask 来处理 HTTP 请求。</p>
<p>首先,让我们从后端开始。我们将定义一个 Flask 应用和两个路由:一个用于显示帖子列表,另一个用于显示单个帖子的详细信息。</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);">from</span><span style="color:var(--shiki-color-text);"> flask </span><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> Flask render_template</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">app </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">Flask</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-constant);">__name__</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">posts </span><span style="color:var(--shiki-token-keyword);">=</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-punctuation);">{</span><span style="color:var(--shiki-token-string-expression);">'id'</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">1</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'title'</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);">'First Post'</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'content'</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);">'This is the first post.'</span><span style="color:var(--shiki-token-punctuation);">}</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-punctuation);">{</span><span style="color:var(--shiki-token-string-expression);">'id'</span><span style="color:var(--shiki-token-punctuation);">:</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">2</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'title'</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);">'Second Post'</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'content'</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);">'This is the second post.'</span><span style="color:var(--shiki-token-punctuation);">}</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-comment);"># Add more posts as needed</span></span>
<span data-line><span style="color:var(--shiki-color-text);">]</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-function);">@app</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">route</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'/'</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">def</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">post_list</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);">return</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">render_template</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'post_list.html'</span><span style="color:var(--shiki-token-punctuation);"> posts</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">posts)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-function);">@app</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">route</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'/post/&lt;int:post_id>'</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">def</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">post_detail</span><span style="color:var(--shiki-color-text);">(</span><span style="color:var(--shiki-token-parameter);">post_id</span><span style="color:var(--shiki-color-text);">):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> post </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">next</span><span style="color:var(--shiki-token-punctuation);">((post </span><span style="color:var(--shiki-token-keyword);">for</span><span style="color:var(--shiki-token-punctuation);"> post </span><span style="color:var(--shiki-token-keyword);">in</span><span style="color:var(--shiki-token-punctuation);"> posts </span><span style="color:var(--shiki-token-keyword);">if</span><span style="color:var(--shiki-token-punctuation);"> post[</span><span style="color:var(--shiki-token-string-expression);">'id'</span><span style="color:var(--shiki-token-punctuation);">] </span><span style="color:var(--shiki-token-keyword);">==</span><span style="color:var(--shiki-token-punctuation);"> post_id) </span><span style="color:var(--shiki-token-constant);">None</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);">if</span><span style="color:var(--shiki-color-text);"> post </span><span style="color:var(--shiki-token-keyword);">is</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">None</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);">return</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">'Post not found'</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">404</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);"> </span><span style="color:var(--shiki-token-function);">render_template</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'post_detail.html'</span><span style="color:var(--shiki-token-punctuation);"> post</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">post)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">if</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">__name__</span><span style="color:var(--shiki-color-text);"> </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);">'__main__'</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> app</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">run</span><span style="color:var(--shiki-token-punctuation);">(debug</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-constant);">True</span><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div>
<p>在这个后端代码中,<code>posts</code> 是一个包含多个帖子的列表,每个帖子都是一个字典,包含一个 ID、一个标题和内容。<code>post_list</code><code>post_detail</code> 函数是两个路由处理器,分别用于显示帖子列表和单个帖子的详细信息。</p>
<p>接下来,让我们看看前端部分。我们将需要两个 Jinja 模板:一个用于显示帖子列表,另一个用于显示单个帖子的详细信息。</p>
<p>post_list.html</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="html" data-theme="default"><code data-language="html" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">&lt;!</span><span style="color:var(--shiki-token-string-expression);">doctype</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">html</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;</span><span style="color:var(--shiki-token-string-expression);">html</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">head</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">title</span><span style="color:var(--shiki-color-text);">>Post List&lt;/</span><span style="color:var(--shiki-token-string-expression);">title</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">head</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">body</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">>Post List&lt;/</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">ul</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% for post in posts %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">li</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">href</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-string-expression);">&quot;{{ url_for('post_detail' post_id=post.id) }}&quot;</span><span style="color:var(--shiki-color-text);">>{{ post.title }}&lt;/</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">li</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% endfor %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">ul</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">body</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/</span><span style="color:var(--shiki-token-string-expression);">html</span><span style="color:var(--shiki-color-text);">></span></span></code></pre></div>
<p>post_detail.html</p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="html" data-theme="default"><code data-language="html" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">&lt;!</span><span style="color:var(--shiki-token-string-expression);">doctype</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">html</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;</span><span style="color:var(--shiki-token-string-expression);">html</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">head</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">title</span><span style="color:var(--shiki-color-text);">>{{ post.title }}&lt;/</span><span style="color:var(--shiki-token-string-expression);">title</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">head</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">body</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">>{{ post.title }}&lt;/</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">p</span><span style="color:var(--shiki-color-text);">>{{ post.content }}&lt;/</span><span style="color:var(--shiki-token-string-expression);">p</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">href</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-string-expression);">&quot;{{ url_for('post_list') }}&quot;</span><span style="color:var(--shiki-color-text);">>Back to Post List&lt;/</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">body</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/</span><span style="color:var(--shiki-token-string-expression);">html</span><span style="color:var(--shiki-color-text);">></span></span></code></pre></div>
<p>在这些模板中,我们使用了 Jinja 的变量、循环和函数。例如,<code>{% for post in posts %}</code> 循环遍历所有的帖子,<code>{{ post.title }}</code> 显示帖子的标题,<code>{{ url_for('post_detail' post_id=post.id) }}</code> 生成帖子详细信息页面的 URL。</p>
<p>这就是一个简单的使用 Flask 和 Jinja 的帖子列表应用示例。你可以根据需要添加更多的功能,例如添加新的帖子、编辑现有的帖子等。</p>
<p>注意,**在 Flask 中Jinja 是默认的模板引擎,**所以你不需要显式创建 Jinja 的环境。如果你的模板不在默认的 <code>templates</code> 文件夹中,你需要在创建 Flask 应用时指定模板文件夹的路径,如下:</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-color-text);">app </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">Flask</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-constant);">__name__</span><span style="color:var(--shiki-token-punctuation);"> template_folder</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-string-expression);">'/path/to/your/templates'</span><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div>
<h3 id="博客应用">博客应用<a aria-hidden="true" tabindex="-1" href="#博客应用" class="internal"> §</a></h3>
<p>以下是一个简单的博客应用示例。首先,我们定义 Flask 应用和路由(<code>app.py</code></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);">from</span><span style="color:var(--shiki-color-text);"> flask </span><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> Flask render_template</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">app </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">Flask</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-constant);">__name__</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-comment);"># 假设我们有以下博客文章</span></span>
<span data-line><span style="color:var(--shiki-color-text);">posts </span><span style="color:var(--shiki-token-keyword);">=</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-punctuation);">{</span><span style="color:var(--shiki-token-string-expression);">&quot;id&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);">1</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;title&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;First Post&quot;</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;content&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;This is the first post.&quot;</span><span style="color:var(--shiki-token-punctuation);">}</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-punctuation);">{</span><span style="color:var(--shiki-token-string-expression);">&quot;id&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);">2</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;title&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;Second Post&quot;</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;content&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;This is the second post.&quot;</span><span style="color:var(--shiki-token-punctuation);">}</span><span style="color:var(--shiki-color-text);"> </span></span>
<span data-line><span style="color:var(--shiki-color-text);">]</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-function);">@app</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">route</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">&quot;/&quot;</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">def</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">home</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);">return</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">render_template</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">&quot;home.html&quot;</span><span style="color:var(--shiki-token-punctuation);"> posts</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">posts)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-function);">@app</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">route</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">&quot;/post/&lt;int:post_id>&quot;</span><span style="color:var(--shiki-token-punctuation);">)</span></span>
<span data-line><span style="color:var(--shiki-token-keyword);">def</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">post_detail</span><span style="color:var(--shiki-color-text);">(</span><span style="color:var(--shiki-token-parameter);">post_id</span><span style="color:var(--shiki-color-text);">):</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> post </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">next</span><span style="color:var(--shiki-token-punctuation);">((post </span><span style="color:var(--shiki-token-keyword);">for</span><span style="color:var(--shiki-token-punctuation);"> post </span><span style="color:var(--shiki-token-keyword);">in</span><span style="color:var(--shiki-token-punctuation);"> posts </span><span style="color:var(--shiki-token-keyword);">if</span><span style="color:var(--shiki-token-punctuation);"> post[</span><span style="color:var(--shiki-token-string-expression);">&quot;id&quot;</span><span style="color:var(--shiki-token-punctuation);">] </span><span style="color:var(--shiki-token-keyword);">==</span><span style="color:var(--shiki-token-punctuation);"> post_id) </span><span style="color:var(--shiki-token-constant);">None</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);">if</span><span style="color:var(--shiki-color-text);"> post </span><span style="color:var(--shiki-token-keyword);">is</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">None</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);">return</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-string-expression);">&quot;Post not found&quot;</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">404</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);"> </span><span style="color:var(--shiki-token-function);">render_template</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">&quot;post_detail.html&quot;</span><span style="color:var(--shiki-token-punctuation);"> post</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">post)</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-token-keyword);">if</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-constant);">__name__</span><span style="color:var(--shiki-color-text);"> </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;__main__&quot;</span><span style="color:var(--shiki-token-punctuation);">:</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> app</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">run</span><span style="color:var(--shiki-token-punctuation);">(debug</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-constant);">True</span><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div>
<p>接着,我们创建一个基础模板(<code>base.html</code></p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="html" data-theme="default"><code data-language="html" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">&lt;!</span><span style="color:var(--shiki-token-string-expression);">DOCTYPE</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">html</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;</span><span style="color:var(--shiki-token-string-expression);">html</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;</span><span style="color:var(--shiki-token-string-expression);">head</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">title</span><span style="color:var(--shiki-color-text);">>{% block title %}{% endblock %}&lt;/</span><span style="color:var(--shiki-token-string-expression);">title</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/</span><span style="color:var(--shiki-token-string-expression);">head</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;</span><span style="color:var(--shiki-token-string-expression);">body</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% block content %}{% endblock %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/</span><span style="color:var(--shiki-token-string-expression);">body</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">&lt;/</span><span style="color:var(--shiki-token-string-expression);">html</span><span style="color:var(--shiki-color-text);">></span></span></code></pre></div>
<p>然后,定义主页模板(<code>home.html</code></p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="html" data-theme="default"><code data-language="html" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">{% extends &quot;base.html&quot; %}</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">{% block title %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> Home</span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endblock %}</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">{% block content %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">>My Blog&lt;/</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">ul</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% for post in posts %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">li</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">href</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-string-expression);">&quot;{{ url_for('post_detail' post_id=post.id) }}&quot;</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {{ post.title }}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">li</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {% endfor %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;/</span><span style="color:var(--shiki-token-string-expression);">ul</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endblock %}</span></span></code></pre></div>
<p>最后,定义文章详情页模板(<code>post_detail.html</code></p>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="html" data-theme="default"><code data-language="html" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">{% extends &quot;base.html&quot; %}</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">{% block title %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> {{ post.title }}</span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endblock %}</span></span>
<span data-line> </span>
<span data-line><span style="color:var(--shiki-color-text);">{% block content %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">>{{ post.title }}&lt;/</span><span style="color:var(--shiki-token-string-expression);">h1</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">p</span><span style="color:var(--shiki-color-text);">>{{ post.content }}&lt;/</span><span style="color:var(--shiki-token-string-expression);">p</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">href</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-string-expression);">&quot;{{ url_for('home') }}&quot;</span><span style="color:var(--shiki-color-text);">>Back to Home&lt;/</span><span style="color:var(--shiki-token-string-expression);">a</span><span style="color:var(--shiki-color-text);">></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endblock %}</span></span></code></pre></div>
<p>在这个 Flask 应用示例中,它显示了一个博客文章列表,你可以点击每个文章的标题来查看文章的详细内容。所有的模板都继承自 <code>base.html</code>,并覆盖了 <code>title</code><code>content</code> 区块。<code>home.html</code> 使用了一个 for 循环来显示所有的文章,<code>post_detail.html</code> 显示了单个文章的标题和内容。</p>
<h3 id="最佳规范">最佳规范<a aria-hidden="true" tabindex="-1" href="#最佳规范" class="internal"> §</a></h3>
<p>编写模板时 ,有一些最佳实践可以提高可维护性:</p>
<ul>
<li>命名规范:如 index.html base.html macros.html</li>
<li>模板结构HTML、逻辑、配置等区块划分清楚</li>
<li>功能模块化:使用宏、包含等复用代码</li>
<li>注释标识:如命名空间、宏参数等</li>
</ul>
<h2 id="高级功能">高级功能<a aria-hidden="true" tabindex="-1" href="#高级功能" class="internal"> §</a></h2>
<h3 id="代码优化">代码优化<a aria-hidden="true" tabindex="-1" href="#代码优化" class="internal"> §</a></h3>
<p>在 Jinja 中,一些优化技术可以帮助你提高模板的性能和可读性。例如:</p>
<ul>
<li>使用宏Macros宏类似于 Python 中的函数,可以帮助你避免重复的代码。</li>
</ul>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="jinja" data-theme="default"><code data-language="jinja" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">{% macro input(name value='' type='text') %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;input type= {{ type }} name= {{ name }} value= {{ value }} ></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endmacro %}</span></span></code></pre></div>
<ul>
<li>使用 include 和 extends <code>include</code><code>extends</code> 可以帮助你复用和组织模板。</li>
</ul>
<div data-rehype-pretty-code-fragment><pre style="background-color:var(--shiki-color-background);" tabindex="0" data-language="jinja" data-theme="default"><code data-language="jinja" data-theme="default"><span data-line><span style="color:var(--shiki-color-text);">{% extends base.html %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% block content %}</span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;h1>{{ title }}&lt;/h1></span></span>
<span data-line><span style="color:var(--shiki-color-text);"> &lt;p>{{ content }}&lt;/p></span></span>
<span data-line><span style="color:var(--shiki-color-text);">{% endblock %}</span></span></code></pre></div>
<h3 id="错误处理">错误处理<a aria-hidden="true" tabindex="-1" href="#错误处理" class="internal"> §</a></h3>
<p>在 Jinja 中错误处理是通过抛出异常实现的。Jinja 定义了一些自己的异常,如 <code>TemplateNotFound</code><code>TemplateSyntaxError</code> 等。主要异常类型有:</p>
<ul>
<li>TemplateNotFound模板文件不存在</li>
<li>TemplateSyntaxError模板语法错误</li>
<li>UndefinedError变量未定义</li>
<li>SecurityError安全错误 (如禁用标签)</li>
</ul>
<p>你可以通过捕捉这些异常来处理错误。</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);">from</span><span style="color:var(--shiki-color-text);"> jinja2 </span><span style="color:var(--shiki-token-keyword);">import</span><span style="color:var(--shiki-color-text);"> TemplateNotFound</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);"> template </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> env</span><span style="color:var(--shiki-token-punctuation);">.</span><span style="color:var(--shiki-token-function);">get_template</span><span style="color:var(--shiki-token-punctuation);">(</span><span style="color:var(--shiki-token-string-expression);">'mytemplate.html'</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);"> TemplateNotFound</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-string-expression);">'Template not found'</span><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div>
<h3 id="测试和调试">测试和调试<a aria-hidden="true" tabindex="-1" href="#测试和调试" class="internal"> §</a></h3>
<p>Jinja 提供了一个强大的模板调试器,可以帮助你查找和修复模板中的错误。你可以通过设置 <code>Environment</code><code>debug</code> 选项来启用调试器。</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-color-text);">env </span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-color-text);"> </span><span style="color:var(--shiki-token-function);">Environment</span><span style="color:var(--shiki-token-punctuation);">(loader</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-punctuation);">... debug</span><span style="color:var(--shiki-token-keyword);">=</span><span style="color:var(--shiki-token-constant);">True</span><span style="color:var(--shiki-token-punctuation);">)</span></span></code></pre></div>
<p><code>debug</code> 选项设置为 <code>True</code>Jinja 会在渲染模板时检查错误,并在发现错误时抛出异常。</p>
<h3 id="集成其他库">集成其他库<a aria-hidden="true" tabindex="-1" href="#集成其他库" class="internal"> §</a></h3>
<p>Jinja 可以与许多其他 Python 库和框架一起使用。例如Jinja 是 Flask 和 Django 这两个流行的 Web 框架的默认模板引擎。此外Jinja 也可以与诸如 Bootstrap 之类的前端框架一起使用,以创建更丰富和动态的网页。</p>
<h2 id="社区动态">社区动态<a aria-hidden="true" tabindex="-1" href="#社区动态" class="internal"> §</a></h2>
<p>Jinja 是一个活跃的开源项目,有一个活跃的开发者和用户社区。你可以在 <a href="https://github.com/pallets/jinja" class="external">Github</a> 上关注 Jinja 的最新更新和发布。此外,你还可以参与 <a href="https://gitter.im/pallets/jinja" class="external">Gitter上的Jinja社区</a>,在那里你可以找到其他 Jinja 用户的帮助,分享你的经验,或者只是去看看其他人都在做什么。</p>
<p>总的来说Jinja 是一个强大而灵活的模板引擎,适合用于多种应用。通过深入学习和实践,你可以充分利用 Jinja 的功能,提高你的 Web 开发效率和质量。</p></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="#安装" data-for="安装">安装</a></li><li class="depth-0"><a href="#核心功能" data-for="核心功能">核心功能</a></li><li class="depth-1"><a href="#创建模板环境" data-for="创建模板环境">创建模板环境</a></li><li class="depth-1"><a href="#定义模板" data-for="定义模板">定义模板</a></li><li class="depth-1"><a href="#渲染模板" data-for="渲染模板">渲染模板</a></li><li class="depth-0"><a href="#实践使用" data-for="实践使用">实践使用</a></li><li class="depth-1"><a href="#帖子应用" data-for="帖子应用">帖子应用</a></li><li class="depth-1"><a href="#博客应用" data-for="博客应用">博客应用</a></li><li class="depth-1"><a href="#最佳规范" data-for="最佳规范">最佳规范</a></li><li class="depth-0"><a href="#高级功能" data-for="高级功能">高级功能</a></li><li class="depth-1"><a href="#代码优化" data-for="代码优化">代码优化</a></li><li class="depth-1"><a href="#错误处理" data-for="错误处理">错误处理</a></li><li class="depth-1"><a href="#测试和调试" data-for="测试和调试">测试和调试</a></li><li class="depth-1"><a href="#集成其他库" data-for="集成其他库">集成其他库</a></li><li class="depth-0"><a href="#社区动态" data-for="社区动态">社区动态</a></li></ul></div></div><div class="backlinks "><h3>Backlinks</h3><ul class="overflow"><li>No backlinks found</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;:&quot;Basics/english&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Blog&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/个人成长&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/医学健康&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/历史&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/哲学宗教&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/心理&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/政治军事&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/教育学习&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/文学&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/生活百科&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/社会文化&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/科学技术&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/经济理财&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/艺术&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Book/计算机&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Company&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Company/信息化&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Company/信息化/规范&quot;,&quot;collapsed&quot;:true},{&quot;path&quot;:&quot;Culture&quot;,&quot;collapse
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