add: proxy pattern

design-patterns/Program.cs

@@ -1,6 +1,7 @@
 using design_patterns.src.Adapter;
 using design_patterns.src.Facade;
 using design_patterns.src.Factory;
+using design_patterns.src.Proxy;
 using design_patterns.src.Singleton;
 using design_patterns.src.Singleton.EcommerceSample;
 
@@ -17,4 +18,7 @@
 FacadeUsage.SampleOne();
 
 Console.WriteLine("\n---------------- Adapter Pattern 🚀");
-AdapterUsage.SampleOne();
+AdapterUsage.SampleOne();
+
+Console.WriteLine("\n---------------- Proxy Pattern 🚀");
+ProxyUsage.SampleOne();

design-patterns/README.md

@@ -20,9 +20,14 @@ In this section, Design patterns in c# will be included.
 
 ![Adapter Pattern](./docs/adapter.png)
 
+### Proxy Pattern
+
+![Proxy Pattern](./docs/proxy.png)
+
 ## Resources
 
 -   https://www.c-sharpcorner.com/UploadFile/8911c4/singleton-design-pattern-in-C-Sharp/
 -   https://www.c-sharpcorner.com/article/factory-design-pattern-in-c-sharp/
 -   https://www.c-sharpcorner.com/article/facade-design-pattern-using-c-sharp/
 -   https://www.c-sharpcorner.com/UploadFile/efa3cf/adapter-design-pattern-in-C-Sharp/
+-   https://www.c-sharpcorner.com/UploadFile/b1df45/proxy-design-pattern-using-C-Sharp/

design-patterns/src/Proxy/ISuperSecretDatabase.cs

@@ -0,0 +1,7 @@
+namespace design_patterns.src.Proxy
+{
+    public interface ISuperSecretDatabase
+    {
+        void DisplayDatabaseName();
+    }
+}

design-patterns/src/Proxy/ProxyUsage.cs

@@ -0,0 +1,12 @@
+namespace design_patterns.src.Proxy
+{
+    public static class ProxyUsage
+    {
+        public static void SampleOne()
+        {
+            Console.WriteLine("\nProxy Usage Sample One : ");
+            ISuperSecretDatabase superSecretDatabase = new SuperSecretDatabaseProxy("test_db", "Password");
+            superSecretDatabase.DisplayDatabaseName();
+        }
+    }
+}

design-patterns/src/Proxy/SuperSecretDatabase.cs

@@ -0,0 +1,15 @@
+namespace design_patterns.src.Proxy
+{
+    /// <summary>
+    /// Super Secret Database
+    /// </summary>
+    public class SuperSecretDatabase(string databaseName) : ISuperSecretDatabase
+    {
+        private readonly string _databaseName = databaseName;
+
+        public void DisplayDatabaseName()
+        {
+            Console.WriteLine("Display database name : " + _databaseName);
+        }
+    }
+}

design-patterns/src/Proxy/SuperSecretDatabaseProxy.cs

@@ -0,0 +1,21 @@
+namespace design_patterns.src.Proxy
+{
+    public class SuperSecretDatabaseProxy(string databaseName, string password) : ISuperSecretDatabase
+    {
+        private SuperSecretDatabase? superSecretDatabase;
+        private readonly string databaseName = databaseName;
+        private readonly string password = password;
+
+        public void DisplayDatabaseName()
+        {
+            if (password.Equals("Password"))
+            {
+                if (superSecretDatabase == null)
+                {
+                    superSecretDatabase = new(databaseName);
+                }
+                superSecretDatabase!.DisplayDatabaseName();
+            }
+        }
+    }
+}