program to read data from file and store data in String

import 'dart:io';

void main() {
  // creating file object
  File file = File('c:\\darttest\\darttest\\test.txt');
  // read file
  String contents = file.readAsStringSync();
  // print file
  print(contents);
}

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program to get information of the file

import 'dart:io';

void main() {
  // open file
  File file = File('c:\\darttest\\darttest\\test.txt');
  // get file location
  print('File path: ${file.path}');
  // get absolute path
  print('File absolute path: ${file.absolute.path}');
  // get file size
  print('File size: ${file.lengthSync()} bytes');
  // get last modified time
  print('Last modified: ${file.lastModifiedSync()}');
}

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program to read only part of file

import 'dart:io';

void main() {
  // open file
  File file = new File('c:\\darttest\\darttest\\test.txt');
  // read only first 10 characters
  String contents = file.readAsStringSync().substring(0, 10);
  // print file
  print(contents);
}

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program to write data to file

import 'dart:io';

void main() {
  // open file
  File file = File('c:\\darttest\\darttest\\test1.txt');
  // write to file
  file.writeAsStringSync('Welcome to test1.txt file.');
  print('File written.');
}

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program to write data to existing file

// dart program to write to existing file
import 'dart:io';

void main() {
  // open file
  File file =  File('c:\\darttest\\darttest\\test.txt');
  // write to file
  file.writeAsStringSync('\nThis is a new content.', mode: FileMode.append);
  print('Congratulations!! New content is added on top of previous content.');
}

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program to delete a file

// dart program to delete file
import 'dart:io';

void main() {
  // open file
  File file = File('c:\\darttest\\darttest\\test1.txt');
  // delete file
  file.deleteSync();
  print('File deleted.');
}

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program to delete a file if file exists

// dart program to delete file if exists
import 'dart:io';

void main() {
  // open file
  File file = File('c:\\darttest\\darttest\\test.txt');
  // check if file exists
  if (file.existsSync()) {
    // delete file
    file.deleteSync();
    print('File deleted.');
  } else {
    print('File does not exist.');
  }
}

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