keep-alive function in Vue3: improve application performance

In Vue3, in order to optimize application performance, a new function called keep-alive is added. This function can cache components to avoid re-rendering when switching, thus improving the overall performance of the application.

1. The role of the keep-alive function

In Vue3, the keep-alive function can be used to cache components and wait for use again. During the rendering process, if a component is not destroyed, there is no need to reinitialize state, recalculate computed properties, etc.

This function receives a name value as a parameter, which is used to specify the component that needs to be cached. The specific usage is as follows:

<template>
  <div>
    <keep-alive>
      <router-view v-if="$route.meta.keepAlive"></router-view>
    </keep-alive>
    <router-view v-if="!$route.meta.keepAlive"></router-view>
  </div>
</template>

Determine which pages need to be cached by specifying the keepAlive field in the meta information of the route.

2. Usage scenarios of keep-alive function

The scenarios where keep-alive function is used are mainly components that require data caching, such as list pages, tab switching, etc.

For example, we have a user list page, and data acquisition takes a long time. We can use the keep-alive function to cache the list page components. When the user returns to the list, the components are obtained directly from the cache to avoid unnecessary errors. Necessary requests to improve user experience.

3. Notes on the keep-alive function

1. Components that use keep-alive caching need to have their own unique identifier. You can add the name attribute to the component, or use the component internal The _id attribute is implemented. Otherwise, an error will be reported due to lack of unique identifier.

2. The cached component will trigger the activated life cycle when it is activated, and the deactivated life cycle will be triggered when it is left.

3. The keep-alive function can only cache the component itself, but not the slot content of the component. If you need to cache slot content, you can add a unique identifier inside the slot and use ref inside the component to obtain the identifier.

4. Summary

Using the keep-alive function in Vue3 can effectively improve the overall performance of the application, especially in scenarios that require frequent switching or a large amount of rendering data. This can be clearly felt to improve performance.

However, when using the keep-alive function, you need to pay attention to the unique identifier of the cache component and the execution of the life cycle, and clean the cache in time to avoid memory leaks.

The above is the detailed content of keep-alive function in Vue3: improve application performance. For more information, please follow other related articles on the PHP Chinese website!