chapter 2: initial samples

Chapter02/working-with-files/readWriteAsync2.js

@@ -0,0 +1,20 @@
+const fs = require('fs');
+const path = require('path')
+
+const filepath = path.join(process.cwd(), 'hello.txt');
+
+fs.readFile(filepath, 'utf8', function (err, contents) {
+    if (err) {
+        return console.log(err);
+    }
+    console.log("File Contents:", contents);
+    contents = contents.toUpperCase();
+    updateFile(filepath, contents);
+});
+
+function updateFile(filepath, contents) {
+    fs.writeFile(filepath, contents, function (err) {
+        if (err) throw err;
+        console.log("File updated.");
+    });
+};