WinForms如何调用按钮上的双击事件？(WinForms how to call a Double-Click Event on a Button?)

 它没有用，因为你手动改变props数组--React不知道它已经改变了。 一般来说，你根本不应该改变道具。 
 
 如果您真的想这样做，可以在componentDidMount中使用setState，然后通过以下方式呈现您的子组件： 
 
class Parent extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      childComponent: null
    }
  }

  componentDidMount() {
    this.setState({ childComponent: <div>Hello</div> });
  }

  render() {
    return (
      <div>
        {this.state.childComponent}
      </div>
    )
  }
}
 
 但是，无论你想做什么，都可能有更好的解决方案。 我无法想象很多情况下你只想在父装载后才能渲染东西。 

It's not working because you are mutating the props array manually - React has no idea that it has changed. In general, you should never change props at all. 
 
If you really want to do this, you can use setState within componentDidMount, and then render your child component through that:
 
class Parent extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      childComponent: null
    }
  }

  componentDidMount() {
    this.setState({ childComponent: <div>Hello</div> });
  }

  render() {
    return (
      <div>
        {this.state.childComponent}
      </div>
    )
  }
}
 
However, there might be a better solution to whatever you're trying to do. I can't imagine many situations in which you'd want to render stuff only after the parent has mounted.