2018-10-10 18:03:03 -04:00
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---
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id: 5a24c314108439a4d4036155
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2020-12-16 00:37:30 -07:00
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title: 发送 Action Data 给 Store
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2018-10-10 18:03:03 -04:00
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challengeType: 6
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2020-09-07 16:16:17 +08:00
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forumTopicId: 301448
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2021-01-13 03:31:00 +01:00
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dashedName: send-action-data-to-the-store
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2018-10-10 18:03:03 -04:00
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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到目前为止,你已经学会了如何将 action dispatch 给 Redux store,但到目前为止,这些 action 并未包含除 `type`之外的任何信息。你还可以发送特定数据和 action 一起。事实上,这是非常常见的,因为 action 通常源于一些用户交互,并且往往会携带一些数据,Redux store 经常需要知道这些数据。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --instructions--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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在代码编辑器中定义了一个基础的`notesReducer()`和`addNoteText()` action creator。完成`addNoteText()`函数的主体,这样它就会返回一个`action`对象。该对象应该包含一个`type`属性,其值为`ADD_NOTE`,还有一个`text`属性通过 action creator 将值设置为`note`。当你调用 action creator 时,你需要传入可以访问该对象的特定注释信息。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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接下来,完成在`notesReducer()`中编写的`switch`语句。你需要添加一个处理`addNoteText()`操作的选项。只要存在`ADD_NOTE`类型的 action,就应该触发 case,并且它应该在传入的`action`上返回`text`属性作为新的`state`
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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这个 action 将在代码底部发送。一旦完成后,运行代码并观察控制台。这就是将特定于 action 的数据发送到 store 并在更新 store `state`时使用它所需的全部内容。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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action creator `addNoteText`应该返回一个包含`type`和`text`的对象。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(
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(function () {
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const addNoteFn = addNoteText('__TEST__NOTE');
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return addNoteFn.type === ADD_NOTE && addNoteFn.text === '__TEST__NOTE';
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})()
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);
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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dispatch 一个 action creator 是`addNoteText`的action`ADD_NOTE`,应将`state`更新为 action creator 传递的字符串。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(
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(function () {
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const initialState = store.getState();
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store.dispatch(addNoteText('__TEST__NOTE'));
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const newState = store.getState();
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return initialState !== newState && newState === '__TEST__NOTE';
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})()
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);
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2018-10-10 18:03:03 -04:00
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```
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2020-08-13 17:24:35 +02:00
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2021-01-13 03:31:00 +01:00
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# --seed--
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## --seed-contents--
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```js
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const ADD_NOTE = 'ADD_NOTE';
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const notesReducer = (state = 'Initial State', action) => {
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switch(action.type) {
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// Change code below this line
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// Change code above this line
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default:
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return state;
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}
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};
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const addNoteText = (note) => {
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// Change code below this line
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// Change code above this line
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};
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const store = Redux.createStore(notesReducer);
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console.log(store.getState());
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store.dispatch(addNoteText('Hello!'));
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console.log(store.getState());
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```
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2020-12-16 00:37:30 -07:00
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# --solutions--
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2021-01-13 03:31:00 +01:00
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```js
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const ADD_NOTE = 'ADD_NOTE';
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const notesReducer = (state = 'Initial State', action) => {
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switch(action.type) {
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// Change code below this line
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case ADD_NOTE:
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return action.text;
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// Change code above this line
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default:
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return state;
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}
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};
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const addNoteText = (note) => {
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// Change code below this line
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return {
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type: ADD_NOTE,
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text: note
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}
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// Change code above this line
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};
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const store = Redux.createStore(notesReducer);
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console.log(store.getState());
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store.dispatch(addNoteText('Hello Redux!'));
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console.log(store.getState());
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```
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