public ViewResult UseFilterExtensionNoFunc()
{
IEnumerable <Product> products = new ShoppingCartInterface()
{
Products = new List <Product>
{
new Product {
Name = "K1", Price = 25.00M, Category = "River"
},
new Product {
Name = "K2", Price = 11.00M, Category = "Estuary"
},
new Product {
Name = "K3", Price = 29.00M, Category = "Lake"
}
}
};
// it can point to any method, as long as the values, a method accepts and returns, match the delegate signature
//using lambda expression without Func
decimal totalFilter = 0;
//extension method that filteres the collection
foreach (Product product in products.Filter(product => product.Category == "Estuary"))
{
totalFilter += product.Price;
}
return(View("Result", (object)String.Format("My shopping cart total with filter without Func is {0}", totalFilter)));
}
public ViewResult UseFilterExtension()
{
IEnumerable <Product> products = new ShoppingCartInterface()
{
Products = new List <Product>
{
new Product {
Name = "K1", Price = 23.00M, Category = "River"
},
new Product {
Name = "K2", Price = 26.00M, Category = "River"
},
new Product {
Name = "K3", Price = 29.00M, Category = "Lake"
}
}
};
decimal totalFilter = 0;
//extension method that filteres the collection, FilterByCategory
foreach (Product product in products.FilterByCategory("Lake"))
{
totalFilter += product.Price;
}
return(View("Result", (object)String.Format("My shopping cart total with filter is {0}", totalFilter)));
}
public ActionResult Index()
{
ShoppingCartInterface cart = new ShoppingCartInterface(calc)
{
Products = products
};
decimal totalValue = cart.CalculateProductTotal();
return(View(totalValue));
}
public ViewResult UseExtensionEnumerable()
{
IEnumerable <Product> products = new ShoppingCartInterface()
{
Products = new List <Product>
{
new Product {
Name = "K1", Price = 23.00M
},
new Product {
Name = "K2", Price = 26.00M
},
new Product {
Name = "K3", Price = 29.00M
}
}
};
//create and populate an array of Product objects
Product[] productArray =
{
new Product {
Name = "K1", Price = 23.00M
},
new Product {
Name = "K2", Price = 26.00M
},
new Product {
Name = "K3", Price = 29.00M
}
};
//extension method in use - TotalPrice()
//due to switch to interface we can use it:
//1. for objects enumerated by IEnumerable<Product>, incl instances of ShoppingCart
//2. for array of Products
decimal cartTotal = products.TotalPrices();
decimal arrayTotal = productArray.TotalPrices();
return(View("Result", (object)String.Format("My shopping cart total is {0} that should equal to total from the array of products {1}", cartTotal, arrayTotal)));
}
