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Table of Contents
Control cache: use of include and exclude
Lifecycle hook changes: activated and deactivated
Scenario recommendations
Home Web Front-end Front-end Q&A Vue Keep-Alive Component for State Preservation

Vue Keep-Alive Component for State Preservation

Jul 12, 2025 am 02:11 AM

Using <keep-alive> in Vue can preserve the status of component switching. 1. Enable cache by wrapping dynamic components in the <keep-alive> tag; 2. Use include and exclude attributes to control the cache range; 3. Components need to define the name attribute and use it with v-if; 4. The cache component will trigger the activated and deactivated life cycle hooks; 5. Applicable to Tab switching, form wizard, search and details pages and other scenarios, but excessive use should be avoided to avoid affecting performance.

Vue Keep-Alive Component for State Preservation

In Vue development, if you want components to retain state when switching (such as form input, scroll position, etc.), <keep-alive></keep-alive> is a very practical built-in component. It allows dynamic components to be not destroyed during switching, thus enabling state cache.

Vue Keep-Alive Component for State Preservation

Basic usage: How to use <keep-alive></keep-alive>

You just need to wrap the components that need to be cached in the <keep-alive></keep-alive> tag:

Vue Keep-Alive Component for State Preservation
 <keep-alive>
  <component :is="currentComponent" />
</keep-alive>

currentComponent here is a dynamic component, such as switching different contents displayed through tabs. Once wrapped in <keep-alive> , these components are not recreated and destroyed when switching, but instead enter a "cache" state.

Control cache: use of include and exclude

Sometimes we don't want to cache all components. At this time, we can use include and exclude attributes to control which components need to be cached.

Vue Keep-Alive Component for State Preservation
  • include : Only cache matching component names
  • exclude : Exclude specified components without cache

For example:

 <keep-alive>
  <component :is="currentComponent" v-if="currentComponent" />
</keep-alive>

Set name attribute in the component definition so that <keep-alive> can recognize:

 export default {
  name: &#39;UserProfile&#39;
}

You can write this way:

 <keep-alive>
  <component :is="currentComponent" v-if="currentComponent" />
</keep-alive>



  




  

Note: v-if is required because <keep-alive> has no effect on v-show .

Lifecycle hook changes: activated and deactivated

When the component is cached by <keep-alive> , its created and mounted will only be executed once. After that, every time you switch back, the activated hook will be triggered; deactivated when leaving.

You can do some cleaning or recovery operations in these two hooks:

 export default {
  activated() {
    console.log(&#39;Component is activated&#39;);
  },
  deactivated() {
    console.log(&#39;Component is cached&#39;);
  }
}

Common uses include:

  • Refetch data in activated (if needed)
  • Clear timer, cancel listening events, etc. in deactivated

Scenario recommendations

Some typical scenarios suitable for using <keep-alive></keep-alive> include:

  • Tab switch pages, such as different subpages in the user center
  • Form Wizard steps to avoid losing input when switching steps
  • Jump between search result page details pages to keep search conditions unchanged

But be careful not to abuse it, because too many components will affect performance. It is recommended to selectively cache key components based on actual needs.


Basically that's it. Rational use of <keep-alive></keep-alive> can significantly improve the user experience, especially in scenarios where components need to be switched frequently.

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