Đọc và Ghi File trong Dart

import 'dart:io';
 
void main() {
  var file = File('example.txt');
  print(file.path);
}

import 'dart:io';
 
void main() {
  var file = File('test.txt');
  
  // Ghi string
  file.writeAsStringSync('Hello, World!');
  
  // Ghi với mode append
  file.writeAsStringSync('\nNew line', mode: FileMode.append);
  
  // Ghi bytes
  file.writeAsBytesSync([72, 101, 108, 108, 111]);
}

import 'dart:io';
 
Future<void> main() async {
  var file = File('test.txt');
  
  await file.writeAsString('Hello, Dart!');
  print('File written successfully');
}

import 'dart:io';
 
void main() {
  var file = File('test.txt');
  
  // Đọc toàn bộ string
  String content = file.readAsStringSync();
  print(content);
  
  // Đọc từng dòng
  List<String> lines = file.readAsLinesSync();
  for (var line in lines) {
    print(line);
  }
  
  // Đọc bytes
  List<int> bytes = file.readAsBytesSync();
  print(bytes);
}

import 'dart:io';
 
Future<void> main() async {
  var file = File('test.txt');
  
  String content = await file.readAsString();
  print(content);
  
  List<String> lines = await file.readAsLines();
  lines.forEach(print);
}

import 'dart:io';
 
void main() {
  var file = File('test.txt');
  
  if (file.existsSync()) {
    print('File exists');
    print('Size: ${file.lengthSync()} bytes');
    print('Modified: ${file.lastModifiedSync()}');
  } else {
    print('File does not exist');
  }
}

import 'dart:io';
 
void main() {
  var dir = Directory('my_folder');
  
  // Tạo directory
  if (!dir.existsSync()) {
    dir.createSync();
  }
  
  // Liệt kê files
  dir.listSync().forEach((entity) {
    if (entity is File) {
      print('File: ${entity.path}');
    } else if (entity is Directory) {
      print('Dir: ${entity.path}');
    }
  });
}

import 'dart:io';
 
void main() {
  var file = File('nonexistent.txt');
  
  try {
    var content = file.readAsStringSync();
    print(content);
  } on FileSystemException catch (e) {
    print('Error: ${e.message}');
    print('Path: ${e.path}');
  }
}

import 'dart:io';
import 'dart:convert';
 
Future<void> main() async {
  var file = File('large_file.txt');
  
  await for (var line in file.openRead()
      .transform(utf8.decoder)
      .transform(LineSplitter())) {
    print(line);
  }
}