reactjs - 使用 TypeScript 在 React.Component 中按名称(字符串)调用函数

Question

我正在使用 TypeScript 编写 React 应用程序。我的组件状态如下所示:

type UploadState = {
  ...
  modal: string | null
  ...
}

在我的render中我有:

render() {
  return <div>{this.renderModal()}</div>
}

我在代码中的某处:

this.setState({ modal: 'mappingModal' })

最后 renderModel 是:

renderModal = () => {
  if (this.state.modal === null) {
    return
  }
  return this[modal as keyof this]() //It doesn't work
}

我希望得到 mappingModal 的返回值:

mappingModal = () => {
  return <h1>Some text or whatever!</h1>
}

但由于 this[modal as keyof this]() 中的 () 而出现此错误:

Cannot invoke an expression whose type lacks a call signature.
Type '{}' has no compatible call signatures.ts(2349)

如果我删除 () 我会在浏览器中收到此错误:

Warning: Functions are not valid as a React child.
This may happen if you return a Component instead of <Component /> from render.
Or maybe you meant to call this function rather than return it.

有什么解决办法吗？

更新(可能的答案)

似乎如果我使用 this[modal as keyof Upload]() - Upload 当然是我的组件名称 - 我不会有任何问题。希望它不会导致任何 future 的错误

Answer 1

似乎如果我使用 this[modal as keyof Upload]() - Upload 当然是我的组件名称 - 我不会有任何问题。像这样:

class Upload extends React.Component<UploadProps, UploadState> {
  ...
  renderModal = () => {
    if (this.state.modal === null) {
      return
    }
    return this[modal as keyof Upload]()
  }
  ...
}