72 lines
1.7 KiB
Plaintext
72 lines
1.7 KiB
Plaintext
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// Classes +
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// Methods +
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// Enums +
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// Loops +
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// Generics (можно использовать List<>) +-
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// Anonymous functions +
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// Future +
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// extension +
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enum Category { PHONE, COMPUTER, TV }
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extension ProductX on Product {
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double get discountedPrice => price * 0.9; // Применяем 10% скидку
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String get fullname => '${name} (${category.name}) - \$${price}';
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}
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class Product {
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String name;
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double price;
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int quantity;
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Category category;
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// Constructor
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Product(this.name, this.price, this.quantity, this.category);
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}
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class Cart {
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final List<Product> items = [];
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void push(Product p) {
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items.add(p);
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}
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double getTotalPrice() {
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double price = 0;
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for (int i = 0; i < items.length; i++) {
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price += items[i].quantity * items[i].price;
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}
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return price;
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}
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int getItemsCount() {
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return items.fold(0, (total, item) => total + item.quantity);
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}
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Future<List<Product>> getItemsAsync() async {
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// Как бы делаем запрос к бэку
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await Future.delayed(Duration(seconds: 3));
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return items;
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}
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}
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void main() {
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Cart cart = Cart();
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Product product = Product('Laptop', 1000.0, 1, Category.COMPUTER);
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cart.push(product);
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cart.push(Product('Smartphone', 500.0, 2, Category.PHONE));
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cart.push(Product('TV', 800.0, 1, Category.TV));
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print('Total price: \$${cart.getTotalPrice()}');
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print('Total items count: ${cart.getItemsCount()}');
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print('Product with discount: ${product.discountedPrice}');
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print('Product fullname: ${product.fullname}');
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Future.delayed(Duration(seconds: 3)).then((_) => print(product.name));
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// List<Product> products = await cart.getItemsAsync();
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// print('Number of elements received from async method: ${products.length}');
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}
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