ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
80 lines
2.7 KiB
Markdown
80 lines
2.7 KiB
Markdown
---
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id: 589fc832f9fc0f352b528e79
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title: 发送和显示聊天消息
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challengeType: 2
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forumTopicId: 301562
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dashedName: send-and-display-chat-messages
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---
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# --description--
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现在，我们可以开始实现聊天室功能了。整体逻辑很简单，只需要获取用户发给服务端的消息，再通过服务端给所有客户端发送信息就可以了。在 client.js 文件里，你应该已经注意到了这段提交表单的代码：
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```js
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$('form').submit(function() {
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/*logic*/
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});
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```
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现在我们需要处理事件的 emit，它应该发生在定义 `messageToSend` 之后，以及清除 `#m` 中的文本之前。我们称这个事件叫 `'chat message'`，需发送的数据叫 `messageToSend`：
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```js
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socket.emit('chat message', messageToSend);
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```
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在服务端，我们需要监听包含 `message` 的 `'chat message'` 事件。一旦事件发生，我们就通过`io.emit` 把包含 `name` 和 `message` 的 `'chat message'` 事件发送给所有已连接的 socket。
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回到客户端，我们需要监听 `'chat message'` 事件。只要接收到这个事件，就把包含名字和消息的内容（注意：需要在名字后添加冒号）通过 `<li>` 添加到 `#messages`。
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至此，我们已经完成发送信息到所有客户端的功能。
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完成上述要求后，你可以在下方提交你的页面链接。如果你遇到了问题，可以参考 [这里](https://gist.github.com/camperbot/d7af9864375207e254f73262976d2016) 的答案。
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# --hints--
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服务端应监听 `'chat message'`，且应在监听到后 emit。
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```js
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(getUserInput) =>
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$.get(getUserInput('url') + '/_api/server.js').then(
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(data) => {
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assert.match(
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data,
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/socket.on.*('|")chat message('|")[^]*io.emit.*('|")chat message('|").*name.*message/gis,
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'Your server should listen to the socket for "chat message" then emit to all users "chat message" with name and message in the data object'
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);
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},
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(xhr) => {
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throw new Error(xhr.statusText);
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}
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);
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```
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客户端应正确处理和展示从 `'chat message'` 事件发来的新数据。
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```js
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(getUserInput) =>
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$.get(getUserInput('url') + '/public/client.js').then(
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(data) => {
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assert.match(
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data,
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/socket.on.*('|")chat message('|")[^]*messages.*li/gis,
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'You should append a list item to #messages on your client within the "chat message" event listener to display the new message'
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);
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},
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(xhr) => {
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throw new Error(xhr.statusText);
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}
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);
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```
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# --solutions--
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```js
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/**
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Backend challenges don't need solutions,
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because they would need to be tested against a full working project.
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Please check our contributing guidelines to learn more.
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*/
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```
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