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Ruby: read a JSON file
Page created: 2025-07-24
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This example reads a JSON file containing an array, parses it, joins the results, and writes them to a text file:
require 'json' jsonf = File.read('names.json') list = JSON.parse(jsonf) # write the array as a comma-separated string joined = list.join(',') File.open('names.txt','w'){ |f| f.write(joined) }
This example reads an Emoji list JSON file and prints a list of the hexcodes from each emoji item, followed by a list of labels:
require 'json' json = File.read('emoji.json') em = JSON.parse(json) hexes = em.map { |e| e['hexcode'] } labels = em.map { |e| e['label'] } puts hexes.join(',') puts labels.join(',')
Structure of the JSON data used by the above example:
[ { "hexcode":"1F1E6", "label":"regional indicator A", "unicode":"🇦" }, ... ]
See also ruby-print-columns for another JSON example