Redux connect (TypeScript 2) 的 mapStateToProps 的正确类型声明

Question

我有一个 Redux 商店并想连接它。这是我的容器组件的摘录：

interface IProps  {
  states: IAppState;
  actions: IAppProps;
}
// mapping state to the props
const mapStateToProps = ( state: IAppState, ownProps = {} ) => ({
  states: state
});
// mapping actions to the props
const mapDispatchToProps = ( dispatch: Redux.Dispatch<IAppState> ) => ({
  actions: Redux.bindActionCreators( actions, dispatch )
});

// connect store to App
@connect<IAppState, IAppProps, any>(
  mapStateToProps,
  mapDispatchToProps
)
export default class App extends React.Component<IProps, {}> {
//...
}

编译时我收到以下问题：

error TS2345: Argument of type '(state: IAppState, ownProps?: {}) => { states: IAppState; }' is not assignable to parameter of type 'MapStateToPropsParam<IAppState, any>'.
  Type '(state: IAppState, ownProps?: {}) => { states: IAppState; }' is not assignable to type 'MapStateToPropsFactory<IAppState, any>'.
    Type '{ states: IAppState; }' is not assignable to type 'MapStateToProps<IAppState, any>'.
      Type '{ states: IAppState; }' provides no match for the signature '(state: any, ownProps?: any): IAppState'.

我正在使用 @types/react-redux@4.4.44 来公开 MapStateToProps 接口。我会认为我的 mapStateToProps 遇到了这个界面......但是有些地方出了问题。有什么想法吗？

Answer 1

好吧，似乎@types/react-redux 接受mapStateToProps 以返回与接收的完全相同的类型。我希望它在映射过程中为道具修改它，例如{ states: AppStateTree }。相反，我修改了状态树combineReducers({ states: myReducer })。所以这段代码工作正常：

interface IRootState {
  state: IAppState;
}

const mapStateToProps = ( state: IRootState ) => state;

const mapDispatchToProps = {
  toggleOpenAddFeed
};

type IProps = IRootState & typeof mapDispatchToProps;

class App extends React.Component<IProps, {}> {
 render() {
    return (
      <div className="main-wrapper">
         <Mycomponent store={this.props} />
      </div>
    );
  }
}

export default connect( mapStateToProps, mapDispatchToProps )( App );

Answer 2

ownProps 没有任何类型。你必须给它一个类型。

const mapStateToProps = ( state: IAppState, ownProps: any = {} )