如何在 React 中使用钩子预初始化状态? [英] How can I pre initialise state with hooks in React?

问题描述

基本上在类组件中，我们在构造函数中预先初始化状态，初始值如下所示.

Basically in class components we pre initialise state in constructor with initial values like below.

     constructor(props){
          super(props);
          this.state = {
                 count: 0
          }
     }

但是在引入钩子之后，所有的类组件都变成了带有状态的功能组件.

But after hooks are introduced all the class components became functional components with state.

但我的查询是如何在 React v16.7.0 中使用钩子将计数状态预初始化为 0

But my query is how can I pre initialise count state to 0 with hooks in React v16.7.0

推荐答案

文档如下:https://reactjs.org/docs/hooks-state.html

文档中的示例显示:

const [count, setCount] = useState(0);

传入 useState 的参数(例如本例中的0")是初始值.

The parameter passed in to useState (e.g. "0" in this case) is the initial value.

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