//index.js
// Node.js program to demonstrate
// the fs.readFile() method
// Include fs module
var fs = require('fs');
// Use fs.readFile() method to read the file
fs.readFile('Demo.txt', 'utf8', function (err, data) {
    // Display the file content
    console.log(data);
console.log('readFile called');
Step to run the Node App:
node index.js
Output: 
readFile called
undefined
Example 2: Below examples illustrate the fs.readFile() method in Node JS:
            JavaScript
    
//index.js
// Node.js program to demonstrate
// the fs.readFile() method
// Include fs module
const fs = require('fs');
// Use fs.readFile() method to read the file
fs.readFile('demo.txt', (err, data) => {
    console.log(data);
Step to run the Node App:
node index.js
Output:
undefined
Error Handling
When using fs.readFile(), it’s important to handle errors properly to prevent crashes and ensure graceful error recovery. Common errors include file not found, insufficient permissions, and I/O errors. You can handle errors by checking the err parameter passed to the callback function. If err is truthy, an error occurred during the reading process, and you should handle it accordingly.
fs.readFile("example.txt", "utf8", (err, data) => {
    if (err) {
        if (err.code === "ENOENT") {
            console.error("File not found:", err.path);
        } else {
            console.error("Error reading file:", err);
        }
        return;
    }
    console.log("File content:", data);
});
Conclusion
The fs.readFile method in Node.js provides a straightforward way to read file contents asynchronously. By understanding its syntax, parameters, usage, and error handling, you can effectively use it to read data from files in your Node.js applications. When working with file I/O operations, always remember to handle errors properly to ensure the reliability and stability of your applications.
                
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