Question

我有一个包含数据数组的状态。某些操作完成后，我需要从该数组中删除所有数据。我使用Angular 2。

const intialState: State = {   
    someData: new Array<someData>()
};

export function stateReducer(state = intialState, action: StateActionList.StateActionList) {
    switch (action.type) {
    case StateActionList.REMOVE_DATA:
            console.log(state.someData);
            return {
                ...state,
                someData: new Array<someData>()
            }
        }
}

在我的组件中，我有以下代码：

this.store.dispatch(new StateActions.RemoveData());

在国家行动中：

export const REMOVE_DATA="REMOVE_DATA";
export class RemoveData implements Action {
    readonly type=REMOVE_DATA;
}

该代码不会为我返回从商店清理数组someData。该数组包含与之前相同的数据

Answer 1

尝试显式返回空数组作为新状态：

case StateActionList.REMOVE_DATA:: {
  return {
    someData: []
  };
}

Answer 2

这看起来有点可疑

someData: new Array<someData>()

someData 是变量名称和类型？

请参阅Declare an array in TypeScript

let arr1: boolean[] = [];
let arr2: boolean[] = new Array();
let arr3: boolean[] = Array();

let arr4: Array<boolean> = [];
let arr5: Array<boolean> = new Array();
let arr6: Array<boolean> = Array();

let arr7 = [] as boolean[];
let arr8 = new Array() as Array<boolean>;
let arr9 = Array() as boolean[];

let arr10 = <boolean[]> [];
let arr11 = <Array<boolean>> new Array();
let arr12 = <boolean[]> Array();

const state = {   
  someData: new Array()
};

console.log('empty', state.someData)
state.someData.push('a')
console.log('contains "a"', state.someData) 

const remove = () =>  {
  console.log('constians "a"', state.someData);
  return {
    ...state,
    someData: new Array()
  }
}

const newState = remove()
console.log('empty', newState.someData)

如何从ngrx商店中删除所有数据？

2 个答案: