奇怪的错误：System.IO.FileNotFoundException：无法加载文件或程序集

Question

I have 2 projects,

The first project C# project where I have a blank form(new project). I am compiling this form as a dll so I can reference the form.

The VB project is an ExcelDNA project which consists of a custom task pane with a button to open the form,the task pane works fine. However, I get the following error when clicking the Button:

System.IO.FileNotFoundException: Could not load file or assembly 

I can get this to work by creating a UserControl in the VB project, and then accessing it via the Button, however I have the form written in C# already and do not want to convert it to VB.

Answer 1

There is no need to convert the project to VB.NET. This error is because the .net runtime cannot find the assembly (dll or exe that contains your first form). In Visual Studio, open the Solution Explorer window and expand the References node. Right-click the reference to your first assembly and click Properties . In the properties window change the Copy Local as True .

This way Visual Studio will copy the assembly to the output folder of the project ('bin\\Debug' or 'bin\\Release').

Answer 2

因此，解决方案是确保将窗体Dll复制到Excel加载项所在的目录中。