How to Fix Element UI's Form Validation Issues in Vue 2 Composition API

Описание: Discover how to resolve form validation problems with Element UI in Vue 2 Composition API while nesting tables for a seamless user experience.
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How to Fix Element UI's Form Validation Issues in Vue 2 Composition API

Creating complex forms that require validation can be challenging, especially when working with Vue 2's Composition API and Element UI. One common issue developers encounter is form validation not functioning as expected. If you've found that your form passes validation even when required fields are empty, you're not alone. In this guide, we'll explore this issue in-depth and provide you with a solution that restores proper validation functionality.

Understanding the Problem

Scenario Description

When building a form that incorporates a nested table structure, you may find yourself facing validation issues. For instance, you might have an el-form component enveloping an el-table, and within the table, you utilize el-form-item for various input fields. Despite following standard validation practices, the validation is not working as intended. When a required field like smName is left blank, the validation still returns 'true', indicating that the form is valid.

Investigation Findings

After troubleshooting, it was discovered that the validation issue stemmed from a problem with how elements were rendered inside the nested structure. Specifically, toggling between different elements (such as div for showing data or el-input for editing) without proper reactivity could confuse the validation logic.

Solution to Restore Validation Functionality

The resolution to this validation quirk lies in how you manage the rendering of elements within your form. By implementing a mechanism to toggle visibility and maintaining proper reactive keys, you can ensure that validation functions correctly during user interactions.

Step-by-Step Solution

1. Identify Your Element Structure

First, analyze how you're structuring your form elements. Ensure that you're using the correct elements based on the mode (view or edit) you're in. Here’s a snippet to illustrate the structure:

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

2. Utilize a Reactive Key for Rendering

To enhance how Vue manages the components, introduce a reactive key that changes whenever the user toggles between view and edit modes. This forces Vue to re-render the form elements correctly.

Here’s how you can implement this in your code:

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

3. Incorporate the Key into Your Form

Make sure to incorporate the formReRenderKey into your el-form component as follows:

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

This change guarantees that Vue will re-evaluate all the properties associated with the el-form whenever the key changes, thus rectifying the validation behavior.

Conclusion

By implementing a reactive key strategy and ensuring proper element structuring, you can overcome the validation issues associated with nested tables in Element UI while using Vue 2's Composition API. This approach reinstates correct validation checks for required fields, leading to a more robust user experience. If you encounter similar challenges in your project, consider this solution as a viable fix to restore functionality and efficiency in your form validations.

Keep exploring and enhancing your Vue development skills, and don’t hesitate to reach out or comment below if you have additional questions or need further clarification!