Скачать или смотреть How to Update a Variable Using Ajax in Your ESP32 Project

Learn how to seamlessly update variables in your ESP32 application using Ajax, ensuring data is refreshed every few seconds without page reloads.
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Updating a Variable Using Ajax in Your ESP32 Project

Are you struggling with updating a variable in your ESP32 project using Ajax? If you're learning Ajax and want to make your web page dynamic, you've come to the right place! This guide will guide you through the process of updating a variable, specifically a random number generated in MicroPython, every two seconds without refreshing the whole page. Let’s dive in!

Understanding the Problem

In your current setup, you're successfully controlling an LED, but you need the displayed variable (rdm) to update continuously without needing to reload the page. This can be achieved using Ajax, which allows you to make asynchronous requests to the server.

Breakdown of the Solution

Here’s how to effectively implement variable updates in your ESP32 web application using Ajax:

Step 1: Setting Up Basic HTML Structure

First, you'll want to ensure your HTML structure is ready. The following snippet provides the framework you need:

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Step 2: Implementing Ajax with JavaScript

To update the variable every two seconds, we need to use Ajax. Here’s a simple approach using XMLHttpRequest. You will also want to make use of setInterval to regularly call your update function:

[[See Video to Reveal this Text or Code Snippet]]

Step 3: Integrating into Your MicroPython Backend

Now, you'll need to set up your MicroPython code to respond to the Ajax request. Ensure it generates a random number and sends that number back as a response. Your backend could look something like this:

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Final Implementation

Here’s what a complete implementation can look like. Make sure to integrate the HTML structure with the JavaScript functions and MicroPython code:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

Using Ajax to update variables in your ESP32 project adds significant interactivity to your application. By implementing the steps outlined above, you can effortlessly refresh the displayed variable without needing to reload the page. So go ahead and apply this to your project, and watch your application come to life!

If you have any questions or need further assistance, feel free to reach out. Happy coding!