Data in Vue.js is a reactive object used to declare and store the state of the component, including: declaring and storing the internal state of the component in a responsive manner; automatically responding to state changes and updating the UI; providing data Binding, easy access and update state; keep state isolated, each component has independent data object.
The role of Data in Vue.js
In Vue.js, data
Is a reactive object that contains the UI state of the component. Its main functions are:
1. Declare and store component state
data
is used to declare and store the internal state of components. These states Changes over time. For example, you could store a boolean value in data
to track whether a component is open.
<code class="js">export default { data() { return { isOpen: false } } }</code>
2. Respond to state changes
Vue.js will respond to any changes in the data
object and update the UI accordingly Content. This means that when you change the state in data
, the UI automatically updates.
For example, when you click a button to set isOpen
to true
, Vue.js automatically displays UI elements related to the open state.
3. Provide data binding
data
Properties in objects can be used as binding expressions in templates. This allows you to easily access and update the component's state in the UI.
For example, the following template binds the isOpen
state and displays the "open" text when the component is open.
<code class="html"><template> <div v-if="isOpen"> <h2>打开</h2> </div> </template></code>
4. Keep state isolated
Each Vue.js component has its own data
object, which helps keep state isolated . This means that the state of one component does not affect the state of another component.
Note:
data
should always be an object, even if it is initially empty. data
The function must return a pure object, which means it is raw and has no methods or reactive properties. The above is the detailed content of The role of data in vue. For more information, please follow other related articles on the PHP Chinese website!