javascript - 在reactjs中使用静态propTypes有什么意义？它能解决任何问题吗？或者它只是一种模式

Question

我正在阅读 Web 应用程序的代码库，并且在代码中看到一些静态 PropType。 我无法理解它解决了什么问题或者为什么需要它们？

这是相同的代码。

static propTypes = {
    fetchCricketFantasyPlayers: PropTypes.func.isRequired,//I see this in action 
     selectedAlpha: PropTypes.array,// this comes from reducer or say redux
     history: PropTypes.object.isRequired // this seems to be related to redirecting etc.
 };

Answer 1

<强> Static 不适合 React，它是 JavaScript 的一部分，根据 MDN 的说法:

The static keyword defines a static method for a class. Static methods aren't called on instances of the class. Instead, they're called on the class itself. These are often utility functions, such as functions to create or clone objects.

这里有两种声明 propTypes 的方法，并且两者的工作方式相同:

class App extends React.Component {
  render() {
    return null
  }
}

App.propTypes = {
  fetchCricketFantasyPlayers: PropTypes.func.isRequired,//I see this in action 
  selectedAlpha: PropTypes.array,// this comes from reducer or say redux
  history: PropTypes.object.isRequired
}

使用静态:

class App extends React.Component {
  static propTypes {
    fetchCricketFantasyPlayers: PropTypes.func.isRequired,//I see this in action 
    selectedAlpha: PropTypes.array,// this comes from reducer or say redux
    history: PropTypes.object.isRequired
  }

  render() {
    return null
  }
}

static 之间的主要区别 和 this 的一点是，您不需要实例化该类来访问该值。