4.14.1: Code Example For Methods As Parameters

Author: faqeerhussein

method_as_parameter.cs

@@ -0,0 +1,69 @@
+
+using System;
+
+class SendingMethodToMethodDemo
+{
+    static void Main()
+    {
+        // Sending Named methods to ReceiverMethod()
+        ReceiverMethod(SquareMethod, "Named");
+        ReceiverMethod(IsEvenMethod, "Named");
+        ReceiverMethod(PrintMessageMethod, "Named");
+
+        // Sending Anonymous methods to ReceiverMethod
+        ReceiverMethod(delegate (int x) { return x * x; }, "Anonymous");
+        ReceiverMethod(delegate (int x) { return x % 2 == 0; }, "Anonymous");
+        ReceiverMethod(delegate (string s) { Console.Write(s); }, "Anonymous");
+
+        // Sending methods using Lambda expression
+        ReceiverMethod(x => x * x, "Lambda");
+        ReceiverMethod(x => x % 2 == 0, "Lambda");
+        ReceiverMethod(s => Console.Write(s), "Lambda");
+    }
+
+    // Named method for demonstration of sending method via Func
+    static int SquareMethod(int x)
+    {
+        return x * x;
+    }
+
+    // Named method for demostration of sending method via Predicate
+    static bool IsEvenMethod(int x)
+    {
+        return x % 2 == 0;
+    }
+
+    // Named method for demonstration of sending method via Action
+    static void PrintMessageMethod(string msg)
+    {
+        Console.Write(msg);
+    }
+
+    // Overloaded Method to execute a Func<int, int> type method
+    static void ReceiverMethod(Func<int, int> parcelMethod, string parcelType)
+    {
+        Console.Write("Received method using " + parcelType);
+        Console.Write(parcelType[0]=='L'? " expression" : " method");
+        Console.Write("-Func: Square of 5 = ");
+        int result = parcelMethod(5);
+        Console.WriteLine(result);
+    }
+
+    // Overloaded Method to execute a Predicate<int> type method
+    static void ReceiverMethod(Predicate<int> parcelMethod, string parcelType)
+    {
+        Console.Write("Received method using " + parcelType);
+        Console.Write(parcelType[0]=='L'? " expression" : " method");
+        Console.Write("-Predicate: Is 4 Even = ");
+        bool result = parcelMethod(4);
+        Console.WriteLine(result);
+    }
+
+    // Overloaded Method to execute an Action<string> type method
+    static void ReceiverMethod(Action<string> parcelMethod, string parcelType)
+    {
+        parcelMethod("Received method using " + parcelType);
+        Console.Write(parcelType[0]=='L'? " expression" : " method");
+        Console.WriteLine("-Action");
+    }
+}

method_as_parameter.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <TargetFramework>net8.0</TargetFramework>
+        <EnableDefaultCompileItems>false</EnableDefaultCompileItems>
+    </PropertyGroup>
+    <ItemGroup>
+        <Compile Include="method_as_parameter.cs" />
+    </ItemGroup>
+  </Project>