public static void Start()
{
var apple = new Product("Apple", Color.Red, Size.Medium);
var tree = new Product("Tree", Color.Green, Size.Large);
var house = new Product("House", Color.Green, Size.Medium);
Product[] products = { apple, tree, house };
var productFilter = new ProductFilter();
Console.WriteLine("Filter by Size {Medium}");
foreach (var item in productFilter.FilterBySize(products, Size.Medium))
{
Console.WriteLine($"- {item.Name}, {item.Color}, {item.Size}");
}
Console.WriteLine("Filter by Color {Green}");
foreach (var item in productFilter.FilterByColor(products, Color.Green))
{
Console.WriteLine($"- {item.Name}, {item.Color}, {item.Size}");
}
Console.WriteLine("Open Close Better filter");
var betterFilter = new BetterFilter();
foreach (var item in betterFilter.Filter(products, new ColorSpecification(Color.Green)))
{
Console.WriteLine($"- {item.Name}, {item.Color}, {item.Size}");
}
Console.WriteLine("Filter by Size {Medium}");
foreach (var item in betterFilter.Filter(products, new SizeSpecification(Size.Medium)))
{
Console.WriteLine($"- {item.Name}, {item.Color}, {item.Size}");
}
Console.WriteLine("Combination");
var andSpecification = new AndSpecification <Product>(
new ColorSpecification(Color.Green),
new SizeSpecification(Size.Medium));
foreach (var item in betterFilter.Filter(products, andSpecification))
{
Console.WriteLine($"- {item.Name}, {item.Color}, {item.Size}");
}
}
static void OpenClosed()
{
var products = new Product[]
{
new Product("Apple", Color.Green, Size.Small),
new Product("Tree", Color.Green, Size.Large),
new Product("House", Color.Blue, Size.Large)
};
Console.WriteLine("Green Products (old filter)");
foreach (Product p in ProductFilter.FilterByColor(products, Color.Green))
{
Console.WriteLine($"\t{p.Name} is {p.Color}");
}
Console.WriteLine("Green Products (better filter)");
var bf = new BetterProductFilter();
foreach (Product p in bf.Filter(products, new ColorSpecification(Color.Green)))
{
Console.WriteLine($"\t{p.Name} is {p.Color}");
}
// Abstracted logic that is open to extension (create new ISpecifications), but closed to modification (should never have to edit BetterProductFilter)
Console.WriteLine("Green & Large Products (better filter)");
var andSpecification = new AndSpecification <Product>(new ColorSpecification(Color.Green), new SizeSpecification(Size.Large));
foreach (Product p in bf.Filter(products, andSpecification))
{
Console.WriteLine($"\t{p.Name} is {p.Color} and {p.Size}");
}
// Abstracted logic that is open to extension (create new ISpecifications), but closed to modification (should never have to edit BetterProductFilter)
Console.WriteLine("Blue or Small Products (better filter)");
var orSpecification = new OrSpecification <Product>(new ColorSpecification(Color.Blue), new SizeSpecification(Size.Small));
foreach (Product p in bf.Filter(products, orSpecification))
{
Console.WriteLine($"\t{p.Name} is {p.Color} and {p.Size}");
}
}
static void Main(string[] args)
{
#region Single Responsability Principle
var j = new Journal();
j.AddEntry("I cried today.");
j.AddEntry("I ate a bug.");
Console.WriteLine(j);
var p = new Persistence();
var filename = @"c:\temp\journal.txt";
p.SaveToFile(j, filename);
Process.Start(filename);
#endregion
#region Open-Closed Principle
var apple = new Product("Apple", Color.Green, Size.Small);
var tree = new Product("Tree", Color.Green, Size.Large);
var house = new Product("House", Color.Blue, Size.Large);
Product[] products = { apple, tree, house };
var pf = new ProductFilter();
Console.WriteLine("Green products (old):");
foreach (var pfp in pf.FilterByColor(products, Color.Green))
{
Console.WriteLine($" - {pfp.Name} is green");
}
// ^^ BEFORE
// vv AFTER
var bf = new BetterFilter();
Console.WriteLine("Green products (new):");
foreach (var pfp in bf.Filter(products, new ColorSpecification(Color.Green)))
{
Console.WriteLine($" - {pfp.Name} is green");
}
Console.WriteLine("Large products");
foreach (var pfp in bf.Filter(products, new SizeSpecification(Size.Large)))
{
Console.WriteLine($" - {pfp.Name} is large");
}
Console.WriteLine("Large blue items");
foreach (var pfp in bf.Filter(products,
new AndSpecification <Product>(new ColorSpecification(Color.Blue), new SizeSpecification(Size.Large)))
)
{
Console.WriteLine($" - {pfp.Name} is big and blue");
}
#endregion
#region Liskov Substitution
Rectangle rc = new Rectangle(2, 3);
Console.WriteLine($"{rc} has area {Area(rc)}");
// should be able to substitute a base type for a subtype
/*Square*/
Rectangle sq = new Square();
sq.Width = 4;
Console.WriteLine($"{sq} has area {Area(sq)}");
#endregion
#region Interface Segregation
#endregion
#region Dependency Inversion
var parent = new Person {
Name = "John"
};
var child1 = new Person {
Name = "Chris"
};
var child2 = new Person {
Name = "Matt"
};
// low-level module
var relationships = new Relationships();
//relationships.AddParentAndChild(parent, child1);
//relationships.AddParentAndChild(parent, child2);
new Research(relationships);
#endregion
Console.ReadKey();
}
