vue array is not enumerable

Vue.js is a popular front-end framework that many developers choose to use to build complex web applications. In Vue.js, you can use arrays to store and manage data. However, some developers may encounter a problem: array properties cannot be tracked by Vue.js.

This is because Vue.js can only track changes in object properties, not array methods. In other words, if you use some methods of the array, Vue.js cannot detect these changes because these methods return a new array instead of modifying the original array.

Fundamentally, the cause of this problem is that Vue.js uses JavaScript's Object.defineProperty method to track changes in object properties. However, this method can only track reads and writes of object properties. It cannot track property deletions and renames, nor can it track changes to arrays.

So, how to solve this problem? There are several ways to solve this problem.

1. Use the mutation methods provided by Vue.js

Vue.js provides some mutation methods to modify arrays, such as push, pop, shift, unshift, splice, sort, reverse, etc. . These methods can directly modify the original array, and Vue.js can automatically track their changes. For example, if you use the push method to add a new element to an array, Vue.js will automatically detect the change and update the view.

2. Use the Vue.set or Vue.delete method

If you use some array methods that do not support Vue.js tracking, you can use the Vue.set or Vue.delete method manually Notify Vue.js of changes to an array. The Vue.set method accepts three parameters: array, index and new value. It inserts the new value at the specified index and notifies Vue.js to update the view. The Vue.delete method also accepts three parameters: the array, the index, and the element to be deleted.

3. Use the Vue.watch property

You can also use Vue.watch to monitor changes in the array. Vue.watch can monitor changes to any Vue.js property, including arrays. However, this approach takes some time and resources because Vue.js needs to recalculate dependencies and update the view every time the array changes.

In short, when developing with Vue.js, try to use the mutation method to modify the array. If you must use an array method that does not support Vue.js tracking, use the Vue.set or Vue.delete method to notify Vue.js of changes to the array. If none of these methods meet your needs, you can use Vue.watch to monitor changes in the array, but you need to pay attention to its performance and resource consumption.

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