[Node.js] Read a File in Node.js with fs.readFile and fs.readFileSync

Posted 2021-01-14 Answer1215

We‘ll read a csv file in node.js both synchronously, and asynchronously. The file we‘re reading is a plain text, utf8 file - but you can also use fs.readFile to read a binary file as a buffer. We‘ll look at the differences between readFile and readFileSync, and show examples of how to catch errors if they occur.

 

const fs = require(‘fs‘)

// Async:

fs.readFile(‘data.csv‘, ‘utf8‘, (err, data) => {
  console.log(data)
})


// Sync:

let results

try {
  // (invalid file error example)
  const data = fs.readFileSync(‘nofile.csv‘, ‘utf8‘)
  results = data  
} catch(e) {
  console.log("error", e)
}

console.log("results", results)