composite pattern

DesignPatternGuru/Composite/Client.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Composite
+{
+	internal class Client
+	{
+		public void ClientCode(Component leaf)
+		{
+			Console.WriteLine($"RESULT: {leaf.Operation()}");
+		}
+
+		public void ClientCode2(Component component1, Component component2)
+		{
+			if (component1.IsComposite())
+				component1.Add(component2);
+
+			Console.WriteLine($"RESULT: {component1.Operation()}");
+		}
+	}
+}

DesignPatternGuru/Composite/Component.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Composite
+{
+	abstract class Component
+	{
+		public abstract string Operation();
+
+		public virtual void Add(Component component)
+		{
+			throw new NotImplementedException();
+		}
+
+		public virtual void Remove(Component component)
+		{
+			throw new NotImplementedException();
+		}
+
+		public virtual bool IsComposite()
+		{
+			return true;
+		}
+	}
+}

DesignPatternGuru/Composite/Composite.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Composite
+{
+	internal class Composite : Component
+	{
+		protected List<Component> _children = new List<Component>();
+
+		public override void Add(Component component)
+		{
+			_children.Add(component);
+		}
+
+		public override void Remove(Component component)
+		{
+			_children.Remove(component);
+		}
+
+		public override string Operation()
+		{
+			int i = 0;
+			StringBuilder sb = new StringBuilder();
+			sb.Append("Branch(");
+
+			foreach (Component component in _children)
+			{
+				sb.Append(component.Operation());
+				if (i != _children.Count - 1)
+					sb.Append("+");
+
+				i++;
+			}
+
+			sb.Append(")");
+			return sb.ToString();
+		}
+	}
+}

DesignPatternGuru/Composite/Composite.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

DesignPatternGuru/Composite/Leaf.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Composite
+{
+	internal class Leaf : Component
+	{
+		public override string Operation()
+		{
+			return "Leaf";
+		}
+
+		public override bool IsComposite()
+		{
+			return false;
+		}
+	}
+}

DesignPatternGuru/Composite/Program.cs

@@ -0,0 +1,36 @@
+namespace Composite
+{
+	internal class Program
+	{
+		static void Main(string[] args)
+		{
+			Client client = new Client();
+
+			// simple leaf
+			Leaf leaf = new Leaf();
+			Console.WriteLine("Client: I get a simple component:");
+			client.ClientCode(leaf);
+			Console.WriteLine("");
+
+			// complex composites
+			Composite tree = new Composite();
+			
+			Composite branch1 = new Composite();
+			branch1.Add(new Leaf());
+			branch1.Add(new Leaf());
+			
+			Composite branch2 = new Composite();
+			branch2.Add(new Leaf());
+			
+			tree.Add(branch1);
+			tree.Add(branch2);
+			Console.WriteLine("Client: Now I've got a composite tree:");
+			client.ClientCode(tree);
+			Console.WriteLine("");
+
+
+			Console.WriteLine("Client: I don't need to check the component classes even when managing the tree:");
+			client.ClientCode2(tree, leaf);
+		}
+	}
+}

DesignPatternGuru/DesignPatternGuru.sln

@@ -17,9 +17,11 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Singleton", "Singleton\Sing
 EndProject
 Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "StructuralPatterns", "StructuralPatterns", "{0B9333EC-FB73-4FEE-B600-9ECCD5A356B1}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Adapter", "Adapter\Adapter.csproj", "{4E8B1160-0BD2-42FD-9DB8-991CAA88578A}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Adapter", "Adapter\Adapter.csproj", "{4E8B1160-0BD2-42FD-9DB8-991CAA88578A}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Bridge", "Bridge\Bridge.csproj", "{60D1EE6E-282D-4613-8B1D-DE355768DCBA}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Bridge", "Bridge\Bridge.csproj", "{60D1EE6E-282D-4613-8B1D-DE355768DCBA}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Composite", "Composite\Composite.csproj", "{8EAAC7FD-ED5E-4567-B1C1-F79AC79C9820}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -55,6 +57,10 @@ Global
 		{60D1EE6E-282D-4613-8B1D-DE355768DCBA}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{60D1EE6E-282D-4613-8B1D-DE355768DCBA}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{60D1EE6E-282D-4613-8B1D-DE355768DCBA}.Release|Any CPU.Build.0 = Release|Any CPU
+		{8EAAC7FD-ED5E-4567-B1C1-F79AC79C9820}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{8EAAC7FD-ED5E-4567-B1C1-F79AC79C9820}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{8EAAC7FD-ED5E-4567-B1C1-F79AC79C9820}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{8EAAC7FD-ED5E-4567-B1C1-F79AC79C9820}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -67,6 +73,7 @@ Global
 		{79AC3F3A-CE95-40C4-94E6-31CC85494E41} = {C470237E-3C3B-49E3-BA4C-86884EC28413}
 		{4E8B1160-0BD2-42FD-9DB8-991CAA88578A} = {0B9333EC-FB73-4FEE-B600-9ECCD5A356B1}
 		{60D1EE6E-282D-4613-8B1D-DE355768DCBA} = {0B9333EC-FB73-4FEE-B600-9ECCD5A356B1}
+		{8EAAC7FD-ED5E-4567-B1C1-F79AC79C9820} = {0B9333EC-FB73-4FEE-B600-9ECCD5A356B1}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {3E5A9C6B-2E8A-466E-B5E0-4379902EFFAC}