How to return an array of lines from a file in node.js ?

In this article, we will return an array of lines from a specified file using node.js. The fs module is used to deal with the file system in node.js and to read file data we use fs.readFileSync( ) or fs.readFile( ) methods. Here we will use the readFileSync method to read the file, and we use the steps below to return the lines of the file in an array:

Using fs.readFileSync and split method

To return an array of lines from a file in Node.js, we will

• Read the data of the file using the fs.readFileSync method, you will get a Buffer
• Convert the Buffer into a string Using the toString( ) method
• Now use the String.split() method to break the data and the delimiter should be "\n"

Example:

Below is the Example in which we are implementing the above steps:

Text file: The gfg.txt file.

Geeksforgeeks
A computer Science Portal for Geeks

Steps to Run the Code: use the following the command

node index.js

Output:

[
 'Geeksforgeeks',
 'A computer Science Portal for Geeks'
]

Using readline for Large Files

This approach uses the readline module to read a file line-by-line, storing each line in an array, which is then returned via a callback function once the file reading is complete.

Example:

Output:

[
 'Geeksforgeeks',
 'A computer Science Portal for Geeks'
]