示例

使用 Node.js 编写的网络服务器示例，它以 'Hello, World!' 响应：

本文档中的命令以 $ 或 > 开头，以复制其在用户终端中的显示方式。 不要包含 $ 和 > 字符。 它们在那里显示每个命令的开始。

不以 $ 或 > 字符开头的行显示上一个命令的输出。

首先，确保已经下载并安装了 Node.js。 有关更多安装信息，请参阅通过包管理器安装 Node.js。

现在，创建一个名为 projects 的空项目文件夹，然后导航到其中。

Linux 和 Mac：

$ mkdir ~/projects
$ cd ~/projects

Windows CMD:

> mkdir %USERPROFILE%\projects
> cd %USERPROFILE%\projects

Windows PowerShell:

> mkdir $env:USERPROFILE\projects
> cd $env:USERPROFILE\projects

接下来，在 projects 文件夹中创建新的源文件并将其命名为 hello-world.js。

在任何首选的文本编辑器中打开 hello-world.js 并粘贴以下内容：

const http = require('http');

const hostname = '127.0.0.1';
const port = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello, World!\n');
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

保存文件，返回终端窗口，输入以下命令：

$ node hello-world.js

这样的输出应该出现在终端中：

Server running at http://127.0.0.1:3000/

现在，打开任何首选的网络浏览器并访问 http://127.0.0.1:3000。

如果浏览器显示字符串 Hello, World!，则表示服务器正在工作。

An example of a web server written with Node.js which responds with 'Hello, World!':

Commands in this document start with $ or > to replicate how they would appear in a user's terminal. Do not include the $ and > characters. They are there to show the start of each command.

Lines that don’t start with $ or > character show the output of the previous command.

First, make sure to have downloaded and installed Node.js. See Installing Node.js via package manager for further install information.

Now, create an empty project folder called projects, then navigate into it.

Linux and Mac:

$ mkdir ~/projects
$ cd ~/projects

Windows CMD:

> mkdir %USERPROFILE%\projects
> cd %USERPROFILE%\projects

Windows PowerShell:

> mkdir $env:USERPROFILE\projects
> cd $env:USERPROFILE\projects

Next, create a new source file in the projects folder and call it hello-world.js.

Open hello-world.js in any preferred text editor and paste in the following content:

const http = require('http');

const hostname = '127.0.0.1';
const port = 3000;

const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello, World!\n');
});

server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

Save the file, go back to the terminal window, and enter the following command:

$ node hello-world.js

Output like this should appear in the terminal:

Server running at http://127.0.0.1:3000/

Now, open any preferred web browser and visit http://127.0.0.1:3000.

If the browser displays the string Hello, World!, that indicates the server is working.