Flask应用出现TemplateSyntaxError，模板继承语法报错求助

Let's break down the issues in your code and fix them step by step:

1. Invalid Jinja2 Template Tag Syntax (The Direct Cause of the Error) #

Your extends tag has two syntax mistakes that are triggering the TemplateSyntaxError:

• You closed it with a single } instead of the required %}. Jinja2 uses {% ... %} for block tags, so the closing syntax must match exactly.
• While not strictly mandatory, adding spaces around extends (like {% extends "layout.html" %}) follows Jinja2's best practices and avoids edge-case parsing issues.

Original broken line:

{%extends "layout.html"}

Fixed line:

{% extends "layout.html" %}

2. Typo in Static Resource Path (Bonus Fix) #

Looking at your truncated image tag, you wrote statkc/im... — that's a clear typo for static, Flask's default directory for static files. To make this more robust (and avoid future path issues), use Flask's url_for helper to reference static files instead of hardcoding the path:

Original (truncated) line:

<img src="statkc/im...

Fixed line using url_for:

<img src="{{ url_for('static', filename='images/your-device-image.jpg') }}" alt="Device preview">

Full Corrected Template Code #

Here's the complete fixed version of your template:

{% extends "layout.html" %} 
{% block content %} 
<main class="hero-section">
  <div class="container">
    <div class="section-content">
      <h2> Discover places near you. </h2>
      <a href="#" class="btn-primary">Sign up</a>
      <a href="#" class="btn-secondary">Learn more</a>
    </div>
    <div class="section-device">
      <img src="{{ url_for('static', filename='images/your-device-image.jpg') }}" alt="Device preview">
    </div>
  </div>
</main>
{% endblock content %}

Quick Reminders #

• Jinja2 is strict about tag syntax — always double-check that block tags ({% ... %}) start with {% and end with %}.
• Using url_for for static files ensures your paths work correctly even if you deploy your app to a subdirectory or adjust your static folder configuration later.

内容的提问来源于stack exchange，提问作者jendellkenner