dart-map.dart

void main() {
  Product p1 = Product(id: 1, name:"test1" , price: 100);
  Product p3 = Product(id: 1, name:"test1" , price: 100);
  Product p2 = Product(id: 1, name:"test2", price: 200);
  
  List<Product> products= new List();
  products.add(p1);
  products.add(p3);
  
  Map<Product,int> cart = {};
  cart[p1] = 10;
  cart[p2] = 20;
  
  cart.forEach((key,item){
    key.printMe();
    print("Value is $item");
  
  });
  print(cart.containsKey(p1));
  
  print(cart.containsKey(products[0]));
  print(cart.containsKey(p3));
  
}
class Product{
  final name;
  final id;
  final price;
  Product({this.id,this.name, this.price});
  
  printMe(){
    print("I am $name");
  }
}