Xamarin Forms Understanding Shared vs .NET Standard Projects Step by step Implementation and Top 10 Questions and Answers
 Last Update: April 01, 2025      10 mins read      Difficulty-Level: beginner

Explaining Xamarin.Forms: Understanding Shared vs. .NET Standard Projects

Introduction

Xamarin.Forms is a powerful and flexible framework for building cross-platform mobile applications using C#. With Xamarin.Forms, you can create applications for iOS, Android, and Windows with a single codebase, reducing duplication and enhancing maintainability. Central to effective Xamarin.Forms development is understanding the two primary project structures: Shared Projects and .NET Standard projects. This guide will walk you through the details of both, helping you choose the right approach for your project.

Prerequisites

Before diving into Shared and .NET Standard projects, ensure you have a foundational understanding of the following concepts:

  • C# Programming Language: Familiarity with C# is essential, as it is the core language used in Xamarin.Forms.
  • Xamarin.Forms Basics: Knowledge of how Xamarin.Forms works, including concepts like pages, layouts, and controls.
  • Visual Studio: Experience with Visual Studio, the primary IDE for Xamarin.Forms development (although you can also use Visual Studio for Mac).

Shared Project

A Shared Project in Xamarin.Forms is a project type that shares code and assets directly in your solution without compiling them into a DLL. Here’s a step-by-step explanation of how it works and its advantages and disadvantages.

1. Creating a Shared Project

  • Step 1: Open Visual Studio and create a new Xamarin.Forms project.
  • Step 2: Choose the option to create a Shared Project for the code-sharing strategy.
  • Step 3: Visual Studio sets up the solution with a shared project included.

2. Structure of a Shared Project

  • Project References: The shared project does not produce a DLL. Instead, its contents (code files, XAML, images, etc.) are directly compiled into the specific platform projects (iOS, Android, UWP).
  • Shared Code: Common code, such as ViewModel classes, services, utilities, and shared XAML, is placed in the shared project.
  • Platform-Specific Code: Any code that requires platform-specific implementation (like accessing device-specific APIs) is implemented in the respective platform project.

3. Advantages of Shared Projects

  • Direct Compilation: The code in a Shared Project is compiled into each platform project, which can potentially lead to better performance since the compiler makes full use of platform-specific optimizations.
  • Less Setup: Setting up a Shared Project is relatively straightforward compared to a .NET Standard project.
  • No Dependency Issues: Shared Projects do not face issues related to dependency management since the code is directly included in each platform project.

4. Disadvantages of Shared Projects

  • Limited IDE Support: Shared Projects do not provide full IDE support like a .NET Standard library, which can lead to less accurate IntelliSense and other code-editing features.
  • No NuGet Packages: You cannot include NuGet packages directly in a Shared Project. Instead, you must add them to each platform project separately.
  • Code Duplication: Shared Projects require platform-specific code to be duplicated across platform projects, which can lead to inconsistent behavior if not managed properly.

.NET Standard Project

A .NET Standard project is a more modern approach to sharing code in Xamarin.Forms applications. Unlike a Shared Project, a .NET Standard library compiles into a DLL, which can be referenced by multiple projects, including the platform-specific projects in a Xamarin.Forms solution.

1. Creating a .NET Standard Project

  • Step 1: Open Visual Studio and create a new Xamarin.Forms project.
  • Step 2: Choose the option to create a .NET Standard Library for the code-sharing strategy.
  • Step 3: Visual Studio sets up the solution with a .NET Standard project included.

2. Structure of a .NET Standard Project

  • Project References: The .NET Standard project compiles into a DLL, which is then referenced by each platform project (iOS, Android, UWP).
  • Shared Code: Common code, such as ViewModel classes, services, utilities, and shared XAML, is placed in the .NET Standard project.
  • Platform-Specific Code: Any code that requires platform-specific implementation (like accessing device-specific APIs) is implemented in the respective platform project.

3. Advantages of .NET Standard Projects

  • IDE Support: .NET Standard libraries are fully supported by Visual Studio, providing accurate IntelliSense and other code-editing features.
  • NuGet Package Management: You can include NuGet packages directly in a .NET Standard library and reference them across all platform projects.
  • Reusability: The DLL compiled from a .NET Standard library can be reused in other projects, such as Xamarin.iOS, Xamarin.Android, UWP, and even .NET desktop applications.
  • Consistency: Platform-specific code can be isolated in individual platform projects, enhancing code consistency and maintainability.

4. Disadvantages of .NET Standard Projects

  • Compilation Overhead: There might be slight performance overhead compared to Shared Projects due to the additional layer of abstraction introduced by the DLL.
  • More Setup: Setting up a .NET Standard project involves more steps compared to a Shared Project, including configuring project references and NuGet package management.

Choosing Between Shared and .NET Standard Projects

When deciding between a Shared Project and a .NET Standard project for your Xamarin.Forms application, consider the following factors:

  • Development Experience: If you prefer a more modern and feature-rich development experience with full IDE support, a .NET Standard project is the better choice.
  • Code Reusability: If you need the capability to reuse code across different types of projects or applications, a .NET Standard project offers better reusability.
  • Setup Complexity: If you want a simpler setup process with minimal configuration, a Shared Project might be more suitable.
  • Performance: In most cases, the performance difference between Shared Projects and .NET Standard projects is negligible. However, if you require the best possible performance, a Shared Project might have a slight edge.
  • NuGet Packages: If your project heavily relies on third-party libraries via NuGet packages, a .NET Standard project is more conducive to managing these dependencies.

Conclusion

Understanding the differences between Shared and .NET Standard projects is crucial for effective Xamarin.Forms development. Shared Projects offer simplicity and direct compilation, while .NET Standard projects provide enhanced IDE support, code reusability, and better NuGet package management. By carefully considering your project’s requirements and development preferences, you can choose the right approach to maximize the benefits of a single-codebase strategy in Xamarin.Forms.

Embrace the power of Xamarin.Forms and its code-sharing capabilities to build robust and efficient cross-platform applications. Remember that the key to success lies not only in choosing the right project type but also in writing clean, maintainable, and well-organized code. Happy coding!

Additional Resources

By leveraging these resources, you can deepen your knowledge of Xamarin.Forms and continuously improve your skills as a developer.