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java-script:read-file [2023/08/04 23:30] odeftajava-script:read-file [2023/08/20 01:19] (current) – ↷ Links adapted because of a move operation 217.113.194.57
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 If you prefer using **Promise** instead of the **onload** event, you can create a wrapper function around the FileReader API that returns a promise. \\  If you prefer using **Promise** instead of the **onload** event, you can create a wrapper function around the FileReader API that returns a promise. \\ 
-A new function readAsText wraps the FileReader API and returns a promise. This promise resolves with the file's contents when the onload event is fired, and rejects if there's an error during the read operation (onerror). Now the readFile function uses this readAsText function and handles the file content in a then clause, which gives a more modern, promise-based way of handling the file reading operation.+A new function **readAsText** wraps the FileReader API and returns a promise. This promise resolves with the file's contents when the onload event is fired, and rejects if there's an error during the read operation (onerror). \\ Now the readFile function uses this readAsText function and handles the file content in a then clause, which gives a more modern, promise-based way of handling the file reading operation.
  
 <code javascript read-file-web-promise.html> <code javascript read-file-web-promise.html>
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 </code> </code>
  
 +===== Read a file in Node.js =====
  
 +First you should [[java-script:node-js:setup|initialize the directory as a node.js es6+ module.]]
  
 +<code javascript fileReader.js>
 +import fs from 'fs/promises';
 +
 +export async function readFile(filePath) {
 +    try {
 +        const data = await fs.readFile(filePath, 'utf8');
 +        console.log('File content:', data);
 +    } catch (err) {
 +        console.error('An error occurred:', err);
 +    }
 +}
 +</code>
 +
 +<code javascript index.js>
 +import { readFile } from './fileReader.js';
 +
 +const fileName = process.argv[2];
 +if (!fileName) {
 +    console.log('Please provide a file name as a command-line argument');
 +    process.exit(1);
 +}
 +
 +readFile(fileName);
 +</code>
 +
 +To run it:
 +<code>
 +node ./index.js C:/test.txt
 +</code>
  
  
  
  
java-script/read-file.1691181029.txt.gz · Last modified: 2023/08/04 23:30 by odefta