Скачать или смотреть How to Filter the Select-Options Field in JavaScript

Discover how to effectively filter select-options fields in JavaScript based on user selections. This guide provides clear code examples and solutions.
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Filtering Select-Options Field in JavaScript

When building web applications, you may find yourself needing to filter select-options based on user interactions. For instance, when a user selects a city, the next drop-down could display corresponding routes, and then filter available positions based on the chosen route.

In this post, we will explore how to achieve this functionality using JavaScript, with clear and actionable examples.

The Problem Scenario

Let’s break down the task. You have three select fields:

City: The user selects a city.

Route: This field is populated based on the selected city.

Position: This field should only display positions relevant to the selected route.

You may have encountered this JavaScript snippet, but it wasn't working as expected:

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

Let’s solve this in a way that ensures your application works smoothly when the user makes selections.

Solution Approaches

We will discuss two different approaches to solve the problem:

1. Hiding Unwanted Options

The first approach involves hiding options not relevant to the selected route using CSS (display: none). Here's how you can do it:

Step 1: HTML Structure

First, ensure you have the following HTML layout for the select fields:

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

Step 2: JavaScript Logic

Now, implement the JavaScript function to handle the changes:

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

2. Rendering Only Selected Options

The second approach involves rendering only the relevant options in the position field based on the selected route.

Step 1: Same HTML Structure

You can use the same HTML structure as before.

Step 2: Updated JavaScript Logic

Replace your JavaScript logic with the following:

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

Conclusion

Both example approaches ensure that the position field dynamically updates based on user selections in a user-friendly way. Feel free to choose either method based on your application needs—hiding unwanted tags or rendering only relevant ones.

By integrating such features, you not only improve user experience but also enhance the functionality of your application. Happy coding!