Target Multiple Frameworks in .NET Core 2.x App

Target Multiple Frameworks in .NET Core 2.x App

Introduction In .NET Core 2.x, you have the flexibility to target multiple frameworks within a single application. This allows you to build applications that can run on different versions of .NET Core or even on different operating systems. In this documentation, we will explore how to target multiple frameworks in a .NET Core 2.x app, along with code examples and explanations.

Prerequisites Before proceeding, ensure that you have the following prerequisites:

• .NET Core 2.x SDK installed on your development machine.
• A text editor or an integrated development environment (IDE) such as Visual Studio Code or Visual Studio.

Step 1: Creating a New .NET Core 2.x App

1. Open your preferred terminal or command prompt.
2. Navigate to the directory where you want to create the app.
3. Run the following command to create a new .NET Core 2.x app:

   javascript
   dotnet new console -n MyMultiFrameworkApp
   

Step 2: Editing the Project File

1. Open the MyMultiFrameworkApp.csproj file in a text editor.
2. Locate the <TargetFramework> element and replace it with the following code:

   xml
   <TargetFrameworks>netcoreapp2.0;net452</TargetFrameworks>
   

   In this example, we are targeting both .NET Core 2.0 and .NET Framework 4.5.2.

Step 3: Writing Code for Multiple Frameworks

1. Open the Program.cs file in your text editor.
2. Add conditional compilation symbols to include or exclude code for different frameworks. Here's an example:

   csharp
   using System;
   
   namespace MyMultiFrameworkApp
   {
       class Program
       {
   #if NETCOREAPP2_0
           static void Main(string[] args)
           {
               Console.WriteLine(".NET Core 2.0");
           }
   #endif
   
   #if NET452
           static void Main(string[] args)
           {
               Console.WriteLine(".NET Framework 4.5.2");
           }
   #endif
       }
   }
   

Step 4: Building and Running the App

1. Open your terminal or command prompt.
2. Navigate to the directory where your MyMultiFrameworkApp.csproj file is located.
3. Run the following command to build and run the app:

   arduino
   dotnet run
   

Explanation In this documentation, we learned how to target multiple frameworks in a .NET Core 2.x app. By editing the project file and specifying multiple target frameworks, you can ensure that your application can run on different versions of .NET Core or .NET Framework. By using conditional compilation symbols, you can include or exclude specific code based on the targeted frameworks.

This approach allows you to maximize the reach of your application and provide compatibility with different runtime environments. It is particularly useful when developing libraries or applications that need to support various platforms or have dependencies on different framework versions.

Remember to test your application thoroughly on each targeted framework to ensure compatibility and optimal performance.