Nodejs entry installation simple book

Node.js is a popular server-side JavaScript programming language. It is fast, efficient and flexible. It has long become one of the preferred languages ​​​​for Node.js developers.

This article will introduce the entry-level installation process of Node.js, as well as some basic usage methods.

Installation of Node.js

First, you need to install Node.js on your computer. In Windows systems, you can download the Node.js installer on the official website and run it to start the installation.

In Mac systems, you can install Node.js by opening a terminal and using Homebrew to run the following command:

$ brew install node

After the installation is complete, you can use the following command to check whether Node is successfully installed .js:

$ node -v

If the Node.js version you installed is displayed, congratulations, you have successfully installed Node.js!

Getting started with Node.js

With Node.js, you can start writing Node.js applications.

Here is an example of a simple Node.js program that will output "Hello World!":

console.log('Hello World!');

Save the above code as "hello.js" and run it with the following command :

$ node hello.js

You will see the output of "Hello World!" on the terminal.

Next, we will extend this simple Node.js program so that it can output some more meaningful content to the terminal.

We can use the "fs" module of Node.js to read and write files. The following is an example of a program using the fs module, which will read a text file and output its contents to the terminal:

const fs = require('fs');

fs.readFile('/path/to/file', 'utf8', (err, data) => {
  if (err) throw err;
  console.log(data);
});

Please save the above code as "readfile.js" and replace "/ path/to/file" with the path to the actual text file you want to read.

Then, run it via the following command:

$ node readfile.js

You will see the contents of the text file you read on the terminal.

Conclusion

Now, you have understood the basic usage and entry-level installation process of Node.js. So simple, does it make you look forward to the future development of Node.js?

Hope this article is helpful to you!

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