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Flask framework installation tutorial: A complete guide from configuring the environment to running the application, specific code examples are required
Introduction:
Flask is a lightweight framework written in Python A large-scale web application framework that is easy to learn, flexible and easy to use, and suitable for developing web applications of various sizes. This article will introduce the installation process of the Flask framework in detail, including configuring the environment, installing dependent libraries and running a simple application, and provide specific code examples.
1. Configuration environment
Before we begin, we first need to configure an environment suitable for developing Flask applications. The specific steps are as follows:
Install virtual environment
In order to isolate the dependent libraries and environments of different projects, we recommend using a virtual environment to develop Flask applications. Run the following command in the command line to install the virtual environment:
pip install virtualenv
Create a virtual environment
Run the following command in the command line to create a virtual environment named "myenv":
virtualenv myenv
Activate virtual environment
Run the following command in the command line to activate the virtual environment:
Windows:
.myenvScriptsctivate
Unix/Linux:
source myenv/bin/activate
#2. Install Flask and dependent libraries
After we have completed the environment configuration, we need to Install Flask and its related dependent libraries. The specific steps are as follows:
Install Flask
Run the following command in the command line to install Flask:
pip install flask
Install other dependent libraries
The Flask framework usually requires some other dependent libraries to support its functionality. Run the following command in the command line to install these libraries:
pip install flask-wtf pip install flask-sqlalchemy pip install flask-login
3. Write a simple Flask application
Once we have installed Flask and its related dependent libraries, we can write A simple Flask application. Here is a simple example:
from flask import Flask, render_template app = Flask(__name__) @app.route('/') def index(): return render_template('index.html') if __name__ == '__main__': app.run(debug=True)
In this example, we create a Flask application named "app" and define a route "/" to return a rendered template" index.html". When we run this application, debug mode will be enabled.
4. Create a template file
In the above example, we mentioned a template file named "index.html". This file is used to display the application interface. Here is a simple "index.html" example:
<!DOCTYPE html> <html> <head> <title>My Flask App</title> </head> <body> <h1>Welcome to My Flask App!</h1> </body> </html>
In this example, we have created a simple HTML page that contains a title and a welcome message.
5. Run the Flask application
Now that we have completed writing a simple Flask application, we can run it. Run the following command in the command line to start the application:
python app.py
When the application starts successfully, you will see an output similar to the following:
* Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
Now, visit "http:/ /127.0.0.1:5000", you will see the application's welcome screen.
Conclusion:
This article introduces the installation process of the Flask framework in detail, including configuring the environment, installing dependent libraries and running a simple application. By following the steps and code examples provided in this article, you can easily start developing your own web applications using Flask. Hope this article is helpful to you!
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