With Examples: How can you Implement Conditional Rendering in Flask Templates?

Updated by Ashirafu Kibalama on April 02, 2024

With Examples Learn: How can you Implement Conditional Rendering in Flask Templates?

Flask, a micro web framework for Python, offers powerful templating capabilities through Jinja2, enabling developers to create dynamic web applications quickly.

One fundamental aspect of web development is conditional rendering, where content is displayed or hidden based on certain conditions.

This blog post delves into the art of implementing conditional rendering in Flask templates.

Improve your Flask skills with effective conditional rendering techniques, whether you are a beginner or an experienced developer.

We will explore how you can use Flask and Jinja2's flexibility to create dynamic and responsive web interfaces that meet your needs.

Conditional rendering in Flask templates can be implemented using Jinja2 templating language, the default template engine in Flask.

With the help of an example, Here's how you can implement Conditional Rendering in Flask templates:

#main.py

from flask import Flask, render_template

app = Flask(__name__)


@app.route('/')
def index():
    user_logged_in = True  # Assuming this variable indicates whether the user is logged in or not
    return render_template('index.html', user_logged_in=user_logged_in)

Then, in your template (index.html), you can use Jinja2's if statement to render content based on the value of the user_logged_in variable conditionally passed from the view:

#index.html

<!DOCTYPE html>
<html>
<head>
    <title>Conditional Rendering</title>
</head>
<body>

    {% if user_logged_in %}
        <p>Welcome, user!</p>
        <!-- Additional content for logged-in users -->
    {% else %}
        <p>Please log in to access the content.</p>
        <!-- Additional content for non-logged in users -->
    {% endif %}

</body>
</html>