我需要从我的屏幕发送动态数据到action/reducer并从API中获取数据,但是当我在我的rootSaga中屈服时,我会得到这样的错误:
检查时未捕获(patternOrChannel):patternOrChannel未定义
rootSaga在rootSaga
takeEvery
错误:take(patternOrChannel):patternOrChannel未定义
屏幕代码:
import { checkUserLoginStatus, userSignin } from '../actions/user';
class PreCheckout extends PureComponent {
handleLogin = () => {
this.props.dispatch(userSignin(username, password));
};
render() { .......
行动:
const USER_SIGNIN = 'USER_SIGNIN';
export const userSignin = (username, password) => ({
type: USER_SIGNIN,
username,
password,
});
减速器:
import {
CHECK_USER_LOGIN_STATUS,
USER_SIGNIN,
USER_SIGNIN_RESULT,
USER_SIGNIN_ERROR,
} from '../actions/user';
const initialState = {
isLoggedIn: false,
isFetching: false,
information: {},
error: null,
};
const reducer = (state = initialState, action) => {
switch (action.type) {
case CHECK_USER_LOGIN_STATUS:
return {
...state,
};
case USER_SIGNIN:
return {
...state,
isFetching: true,
};
case USER_SIGNIN_RESULT:
return {
...state,
isFetching: false,
information: action.result,
};
case USER_SIGNIN_ERROR:
return {
...state,
isFetching: false,
error: action.error,
};
Redux-Saga:
import {
USER_SIGNIN,
USER_SIGNIN_RESULT,
USER_SIGNIN_ERROR,
} from '../actions/user';
function* fetchUserInformation(action) {
try {
console.log('fetchUserInformation action: ', action);
const response = yield call(login, action);
yield put({
type: USER_SIGNIN_RESULT,
result: response.result,
});
} catch (e) {
yield put({
type: USER_SIGNIN_ERROR,
error: e.message,
});
}
}
export default function* rootSaga() {
yield takeEvery(USER_SIGNIN, fetchUserInformation);
}
3条答案
按热度按时间yfjy0ee71#
正如我在注解中提到的,你只是忘记了导出常量。
应该是
或者
这些类型的bug可以通过启用rule的
eslint-plugin-import
使用eslint-plugin-import
捕获。nhaq1z212#
USER_SIGNIN
可能未定义。jxct1oxe3#
如果有人使用TypeScript:当将reducer操作定义为
enum
时,请确保将每个枚举项的默认值替换为字符串,例如: