کار با SQLite و دیتابیس آفلاین در فلاتر

dependencies:
  flutter:
    sdk: flutter
  sqflite:
  path:

import 'dart:async';
import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';

class Dog {
  final int id;
  final String name;
  final int age;

  Dog({this.id, this.name, this.age});
}

final Future<Database> database = openDatabase(
  
  join(await getDatabasesPath(), 'doggie_database.db'),
);

final Future<Database> database = openDatabase(
  
  join(await getDatabasesPath(), 'doggie_database.db'),
 
  onCreate: (db, version) {
   
    return db.execute(
      "CREATE TABLE dogs(id INTEGER PRIMARY KEY, name TEXT, age INTEGER)",
    );
  },
 
  version: 1,
);

class Dog {
  final int id;
  final String name;
  final int age;

  Dog({this.id, this.name, this.age});

  
  Map<String, dynamic> toMap() {
    return {
      'id': id,
      'name': name,
      'age': age,
    };
  }
}


Future<void> insertDog(Dog dog) async {
 
  final Database db = await database;

  await db.insert(
    'dogs',
    dog.toMap(),
    conflictAlgorithm: ConflictAlgorithm.replace,
  );
}

final fido = Dog(
  id: 0,
  name: 'Fido',
  age: 35,
);

await insertDog(fido);

Future<List<Dog>> dogs() async {

  final Database db = await database;


  final List<Map<String, dynamic>> maps = await db.query('dogs');


  return List.generate(maps.length, (i) {
    return Dog(
      id: maps[i]['id'],
      name: maps[i]['name'],
      age: maps[i]['age'],
    );
  });
}


print(await dogs()); 

Future<void> updateDog(Dog dog) async {

  final db = await database;


  await db.update(
    'dogs',
    dog.toMap(),
 
    where: "id = ?",

    whereArgs: [dog.id],
  );
}


await updateDog(Dog(
  id: 0,
  name: 'Fido',
  age: 42,
));


print(await dogs()); 

Future<void> deleteDog(int id) async {

  final db = await database;


  await db.delete(
    'dogs',
   
    where: "id = ?",
 
    whereArgs: [id],
  );
}

import 'dart:async';

import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';

void main() async {
  final database = openDatabase(
    
    join(await getDatabasesPath(), 'doggie_database.db'),

    onCreate: (db, version) {
      return db.execute(
        "CREATE TABLE dogs(id INTEGER PRIMARY KEY, name TEXT, age INTEGER)",
      );
    },
   
    version: 1,
  );

  Future<void> insertDog(Dog dog) async {

    final Database db = await database;


    await db.insert(
      'dogs',
      dog.toMap(),
      conflictAlgorithm: ConflictAlgorithm.replace,
    );
  }

  Future<List<Dog>> dogs() async {

    final Database db = await database;


    final List<Map<String, dynamic>> maps = await db.query('dogs');


    return List.generate(maps.length, (i) {
      return Dog(
        id: maps[i]['id'],
        name: maps[i]['name'],
        age: maps[i]['age'],
      );
    });
  }

  Future<void> updateDog(Dog dog) async {

    final db = await database;


    await db.update(
      'dogs',
      dog.toMap(),

      where: "id = ?",

      whereArgs: [dog.id],
    );
  }

  Future<void> deleteDog(int id) async {

    final db = await database;


    await db.delete(
      'dogs',
  
      where: "id = ?",

      whereArgs: [id],
    );
  }

  var fido = Dog(
    id: 0,
    name: 'Fido',
    age: 35,
  );


  await insertDog(fido);


  print(await dogs());


  fido = Dog(
    id: fido.id,
    name: fido.name,
    age: fido.age + 7,
  );
  await updateDog(fido);


  print(await dogs());


  await deleteDog(fido.id);

 
  print(await dogs());
}

class Dog {
  final int id;
  final String name;
  final int age;

  Dog({this.id, this.name, this.age});

  Map<String, dynamic> toMap() {
    return {
      'id': id,
      'name': name,
      'age': age,
    };
  }


  @override
  String toString() {
    return 'Dog{id: $id, name: $name, age: $age}';
  }
}