load json from file javascript code example

Example 1: java load .json file

import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;
import org.apache.commons.io.IOUtils; 

    public class JsonParsing {

        public static void main(String[] args) throws Exception {
            InputStream is = 
                    JsonParsing.class.getResourceAsStream( "sample-json.txt");
            String jsonTxt = IOUtils.toString( is );

            JSONObject json = (JSONObject) JSONSerializer.toJSON( jsonTxt );        
            double coolness = json.getDouble( "coolness" );
            int altitude = json.getInt( "altitude" );
            JSONObject pilot = json.getJSONObject("pilot");
            String firstName = pilot.getString("firstName");
            String lastName = pilot.getString("lastName");

            System.out.println( "Coolness: " + coolness );
            System.out.println( "Altitude: " + altitude );
            System.out.println( "Pilot: " + lastName );
        }
    }

Example 2: read json file into object javascript

fs.readFile(filePath, function (error, content) {
    var data = JSON.parse(content);
    console.log(data.collection.length);
});

Example 3: read json from file js

const fs = require('fs');

fs.readFile('./customer.json', 'utf8', (err, jsonString) => {
  if (err) {
    console.log("File read failed:", err)
    return 
  }
  console.log('File data:', jsonString)
})

Example 4: parse local json file

// pure javascript
let object;
let httpRequest = new XMLHttpRequest(); // asynchronous request
httpRequest.open("GET", "local/path/file.json", true);
httpRequest.send();
httpRequest.addEventListener("readystatechange", function() {
    if (this.readyState === this.DONE) {
      	// when the request has completed
        object = JSON.parse(this.response);
    }
});