我正在尝试使用 typescript 获取 react-redux 应用程序,但我一直在围绕相同的错误盘旋。以下代码编译并产生预期结果
// State definition
interface HelloWorldState {
clickCount: number
}
interface AppState extends HelloWorldState {}
// Props definitions
interface HelloWorldProps {
count: number
}
// Actions
const CLICK = 'CLICK';
const click = () => {return {type:CLICK}};
// Reducers
function clickCount(state:number = 0, action:Action) {
if (typeof state === 'undefined') {
return 0;
}
switch (action.type) {
case CLICK:
return state + 1;
default:
return state;
}
}
let rootReducer = combineReducers({
clickCount
});
// Store
let store = createStore(rootReducer);
// Components
class HelloWorld extends React.Component<any, any> {
render() {
return <div onClick={this.handleClick.bind(this)}>Hello world "{this.props.count}"</div>
}
handleClick() {
store.dispatch(click())
}
}
// Container components
const mapStateToProps = (state:AppState):HelloWorldState => {
return Immutable.fromJS({
count: state.clickCount
})
};
const ConnectedHelloWorld = connect(
mapStateToProps
)(HelloWorld);
render(
<Provider store={store}>
<ConnectedHelloWorld/>
</Provider>,
container
);
伟大的!但我使用的是 TypeScript,因为我想在编译时进行类型检查。类型检查最重要的是 state 和 props。所以,而不是class HelloWorld extends React.Component<any, any>
,我想做class HelloWorld extends React.Component<HelloWorldProps, any>
。但是,当我这样做时,我从调用中得到以下编译错误render
TS2324:Property 'count' is missing in type 'IntrinsicAttributes & IntrinsicClassAttributes<HelloWorld> & HelloWorldProps & { children?: React...'.
我真的不明白为什么。count
IS目前在HelloWordProps
定义,它是由减速机提供的,所以我应该没事吧?类似的问题表明这是一个推理问题,我应该声明调用的类型connect
,但我似乎无法找出如何
包.json
{
"name": "reacttsx",
"scripts": {
"build": "webpack"
},
"devDependencies": {
"ts-loader": "^1.3.3",
"typescript": "^2.1.5",
"webpack": "^1.14.0",
"typings": "^2.1.0"
},
"dependencies": {
"es6-promise": "^4.0.5",
"flux": "^3.1.2",
"immutable": "^3.8.1",
"isomorphic-fetch": "^2.2.1",
"jquery": "^3.1.1",
"react": "^15.4.2",
"react-dom": "^15.4.2",
"react-redux": "^5.0.2",
"redux": "^3.6.0",
"redux-logger": "^2.7.4",
"redux-thunk": "^2.2.0"
}
}
打字.json
{
"dependencies": {
"flux": "registry:npm/flux#2.1.1+20160601175240",
"immutable": "registry:npm/immutable#3.7.6+20160411060006",
"react": "registry:npm/react#15.0.1+20170104200836",
"react-dom": "registry:npm/react-dom#15.0.1+20160826174104",
"react-redux": "registry:npm/react-redux#4.4.0+20160614222153",
"redux-logger": "registry:dt/redux-logger#2.6.0+20160726205300",
"redux-thunk": "registry:npm/redux-thunk#2.0.0+20160525185520"
},
"globalDependencies": {
"es6-promise": "registry:dt/es6-promise#0.0.0+20160726191732",
"isomorphic-fetch": "registry:dt/isomorphic-fetch#0.0.0+20170120045107",
"jquery": "registry:dt/jquery#1.10.0+20170104155652",
"redux": "registry:dt/redux#3.5.2+20160703092728",
"redux-thunk": "registry:dt/redux-thunk#2.1.0+20160703120921"
}
}
更新
由于它抱怨count
丢失了,我尝试更新到
render(
<Provider store={store}>
<ConnectedHelloWorld count={0}/>
</Provider>,
container
);
这解决了这个问题。所以问题是编译器不知道Provider
正在提供计数。提供者使用商店。存储应该具有由容器组件clickCount
映射到的值count
。
我注意到我忘记了商店的初始状态。因此,即使类型已检出,状态也会为空。我将其更新为
// Store
let initialState:AppState = {clickCount: 0};
let store = createStore(rootReducer, initialState);
现在我确定clickCount
商店中的设置正确。所以我希望mapStateToProps
函数按照指定的方式获取AppState
并返回HelloWorldProps
,然后Provider
应该提供计数值。这是真的,但编译器没有看到。
那么如何补救呢?