如何在多个项目中直接引用本地myFuncions.cs源文件（非import方式）？

Got it, let's break this down—you want to reuse your myFunctions.cs file (stored locally at D:\myFunctions.cs) across different .NET solutions/projects, without copying it into each project or using assembly references. The goal is to keep it in sync automatically as you update it daily, right? Here's exactly how to do this:

Method 1: Using Visual Studio GUI (Easiest for Visual Studio Users) #

• Open the target project in Visual Studio.
• Right-click the project name in the Solution Explorer, then select Add > Existing Item.
• Navigate to D:\myFunctions.cs in the file picker.
• Instead of clicking the standard Add button, click the small dropdown arrow next to it and choose Add As Link.

This adds a reference to the original file in your project, not a copy. Any changes you make to the original myFunctions.cs will automatically reflect in all projects that link to it—no need to manually update each project.

Method 2: Manually Edit the .csproj File (Great for Non-Visual Studio or Batch Setup) #

If you prefer working with project files directly, or need to set this up across multiple projects quickly:

• Open the target project's .csproj file in a text editor (like Notepad, VS Code, etc.).
• Add the following XML snippet inside the root <Project> node:

<ItemGroup>
  <Compile Include="D:\myFunctions.cs" Link="myFunctions.cs" />
</ItemGroup>

• The Link attribute is optional—it just controls how the file appears in your project's Solution Explorer (you can name it something else or even place it in a virtual folder, e.g., Link="Shared\myFunctions.cs"). The actual source file remains at D:\myFunctions.cs.

Key Notes to Keep in Mind #

• Path Accessibility: Make sure all projects that link to the file can access the D:\ path. If you ever move the file, you'll need to update the path in each project's link/.csproj entry.
• Namespace Consistency: Ensure the namespace in myFunctions.cs matches what your projects expect, or use fully qualified names to call the methods (no extra using directives needed unless you want to simplify code).
• Automatic Sync: Every time you modify myFunctions.cs, simply recompile the projects that link to it—they'll pull in the latest version automatically.

内容的提问来源于stack exchange，提问作者T.Todua