咨询：RevitPlugin 2021及RevitPlugin.exe缺少合适Main方法的技术问题

Hey there, let's fix this frustrating issue you're hitting with your Revit 2021 plugin. The error about missing a static Main method comes from a common misunderstanding: Revit plugins aren't standalone executable apps—they're class libraries that Revit loads and runs at runtime, so a Main entry point isn't just unnecessary, it's irrelevant here. Here's how to resolve this step by step:

1. Check and Correct Your Project Output Type #

This is the most likely root cause:

• Right-click your RevitPlugin project in Solution Explorer → Select Properties
• Go to the Application tab (in Visual Studio)
• Make sure the Output type is set to Class Library (not "Console Application" or "Windows Forms Application"). If it was set to an executable type, Visual Studio expects a Main method to launch the app, which doesn't apply to Revit plugins.

2. Ensure Your Plugin Uses the Correct Revit API Entry Point #

Revit plugins use the IExternalCommand interface as their entry point, not a Main method. Here's a minimal working example to reference:

using Autodesk.Revit.Attributes;
using Autodesk.Revit.DB;
using Autodesk.Revit.UI;

namespace RevitPlugin
{
    [Transaction(TransactionMode.Manual)] // Required for modifying Revit documents
    public class MyPluginCommand : IExternalCommand
    {
        public Result Execute(ExternalCommandData commandData, ref string message, ElementSet elements)
        {
            // Your plugin logic goes here
            TaskDialog.Show("Success", "Revit Plugin Loaded!");
            return Result.Succeeded;
        }
    }
}

3. Clean and Rebuild Your Solution #

After fixing the project type:

• Go to the Build menu → Select Clean Solution to remove any old executable files
• Then select Rebuild Solution to generate the correct .dll file (Revit only loads .dll plugins, not .exe files)

Quick Additional Tips #

• Double-check that you've referenced the correct Revit API assemblies (usually found in your Revit 2021 installation directory: RevitAPI.dll and RevitAPIUI.dll)
• Make sure your project targets the correct .NET framework version compatible with Revit 2021 (it uses .NET Framework 4.8)

内容的提问来源于stack exchange，提问作者ARJUN SINGH YADAV