Question

我得到了错误：

ERROR in src/app/account/account.reducers.ts(24,37): error TS2339: Property 'accounts' does not exist on type '{ account: Account; } | { accounts: Account[]; }'.
  Property 'accounts' does not exist on type '{ account: Account; }'.

这是指reducer中适配器上的addAll行：

export interface AccountState extends EntityState<Account> {
  allAccountsLoaded : boolean;
}

export const adapter : EntityAdapter<Account> = createEntityAdapter<Account>();

export const initialAccountState: AccountState = adapter.getInitialState({
  allAccountsLoaded: false
});

export function accountReducer(state = initialAccountState, action: AccountActions): AccountState {
  switch(action.type) {
    case AccountActionTypes.AccountLoaded:
      adapter.addOne(action.payload.account, state);

    case AccountActionTypes.AllAccountsLoaded:
      adapter.addAll(action.payload.accounts, {...state, allAccountsLoaded: true});
    default: {
      return state;
    }
  }
}

但是当我看一下减速器的相关动作时，它们传递的有效载荷是一个以道具名称为“ accounts”的帐户数组。

export class AllAccountsLoaded implements Action {
  readonly type = AccountActionTypes.AllAccountsLoaded;

  constructor(public payload: {accounts: Account[]}) {
  }
}

因此，似乎应该正确传递有效负载。令我担心的是该错误的一部分：'{account：Account; } | {个帐户：帐户[]； }'。我已经看到Ngrx抛出这种错误，如果我在可观察到的效果中错误地键入更改事件名称之一的错误，但我已经对其进行了检查，并且它看起来不错，第一个视图：

  @Effect()
  loadAllAccounts$ = this.actions$
  .pipe(
    ofType<AllAccountsRequested>(AccountActionTypes.AllAccountsRequested),
    withLatestFrom(this.store.pipe(select(allAccountsLoaded))),
    filter(([action, allAccountsLoaded]) => !allAccountsLoaded),
    mergeMap(() => this.accountService.getUserAccounts()),
    map(accounts => new AllAccountsLoaded({accounts}))
  );

Answer 1

好的。如果有人碰到这个。该错误信息非常容易引起误解。如果您看一看减速器的定义：

export function accountReducer(state = initialAccountState, action: AccountActions): AccountState {
  switch(action.type) {
    case AccountActionTypes.AccountLoaded:
      adapter.addOne(action.payload.account, state);

    case AccountActionTypes.AllAccountsLoaded:
      adapter.addAll(action.payload.accounts, {...state, allAccountsLoaded: true});
    default: {
      return state;
    }
  }
}

您会注意到，在适配器存储库样式函数附近您缺少return子句，因此应该是：

return adapter.addAll(action.payload.accounts, {...state, allAccountsLoaded: true});

这只是一个错字，但由于错误将您指向完全不同的方向，因此可能需要您花一些时间来查找。

减速器，实体适配器：类型上不存在属性“帐户”-Angular 7，Rxjs 6，Ngrx

1 个答案: