How to read a local text file?

Question

I’m trying to write a simple text file reader by creating a function that takes in the file’s path and converts each line of text into a char array, but it’s not working.

Answer 1

After the introduction of fetch api in javascript, reading file contents could not be simpler.

reading a text file

fetch('file.txt')
  .then(response => response.text())
  .then(text => console.log(text))
  // outputs the content of the text file

reading a json file

fetch('file.json')
  .then(response => response.json())
  .then(jsonResponse => console.log(jsonResponse))     
   // outputs a javascript object from the parsed json

Update 30/07/2018 (disclaimer):

This technique works fine in Firefox, but it seems like Chrome's fetch implementation does not support file:/// URL scheme at the date of writing this update (tested in Chrome 68).

Update-2 (disclaimer):

This technique does not work with Firefox above version 68 (Jul 9, 2019) for the same (security) reason as Chrome: CORS request not HTTP. See https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS/Errors/CORSRequestNotHttp.