How to Persist Data Sent to a Pug Template in Express скачать в хорошем качестве

How to Persist Data Sent to a Pug Template in Express

Learn how to effectively integrate server-rendered data with client-side JavaScript in your Pug templates using Express. --- This video is based on the question https://stackoverflow.com/q/69547116/ asked by the user 'dan' ( https://stackoverflow.com/u/1368463/ ) and on the answer https://stackoverflow.com/a/69573432/ provided by the user 'Old Geezer' ( https://stackoverflow.com/u/936293/ ) at 'Stack Overflow' website. Thanks to these great users and Stackexchange community for their contributions. Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Persist data sent to a Pug template via render Also, Content (except music) licensed under CC BY-SA https://meta.stackexchange.com/help/l... The original Question post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license, and the original Answer post is licensed under the 'CC BY-SA 4.0' ( https://creativecommons.org/licenses/... ) license. If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com. --- Introduction Working with Pug templates in an Express environment is a common requirement for web developers. One striking challenge developers often face is persisting data that is sent to a Pug template via the res.render() method. In this post, we’ll delve into how to effectively use that data, not just at render time but also after the page has loaded, particularly within client-side functions or event handlers. Understanding the Problem When sending data from your server to a Pug template, you may want to use that same data later on - perhaps when a user interacts with dropdown menus or other form elements. In our scenario, we pass JSON data representing table names and field names: [[See Video to Reveal this Text or Code Snippet]] Our objective is to create two dropdown fields: A dropdown to select a table name. A dynamic second dropdown that shows corresponding field names based on the selected table. While we can easily render the first dropdown at the server-side, the challenge arises in making the data accessible to client-side JavaScript. The Solution The key to solving this issue is understanding the distinction between server-side rendering and client-side scripting. While Pug is primarily used for rendering views at the server, it’s possible to expose server data to client-side JavaScript. Step-by-Step Guide 1. Updating the Express Route First, ensure that your Express route sends the JSON data correctly. Here’s a simplified version: [[See Video to Reveal this Text or Code Snippet]] 2. Creating a Pug Template In your testdata.pug, you can generate a dropdown from the data directly and prepare to manage another dropdown with JavaScript. [[See Video to Reveal this Text or Code Snippet]] 3. Key Points to Note: In the above code, we have two dropdowns: one created by Pug and another by JavaScript on the client-side. On line 18, we use JSON.stringify(data) to convert the server data into a string format that can be parsed by JavaScript. Be cautious with variable naming. The data used in line 18 refers to the server object passed to the Pug script, while the data variable within the JavaScript context references the newly created array. Example of Variable Scoping: Server Side: data passed into res.render() is used to render the template. Client Side: let data creates a new variable that exists only in the JavaScript environment, allowing you to manipulate it freely. Conclusion With these steps, you can successfully persist and utilize data sent from the server to a Pug template in your client-side JavaScript. This approach ensures that users can interact with dynamic options based on previous selections, leading to a more fluid and responsive user experience. By properly integrating server-rendered data into your JavaScript environment, you have achieved a clear pathway to responsive dropdowns and other interactive elements on your web page. Wrapping Up Don't hesitate to experiment with various data shapes as you move forward with your projects. Understanding how to share state between server and client is a powerful skill that will enhance your capability as a web developer.