我有一个C＃Excel加载项目MyExcelAddIn，有一个公共方法foo（）做复杂的东西。出于测试目的，外接还定义了一个工具栏按钮，这是有线美孚（）这样我就可以测试一下，并验证单击按钮调用foo（）和做什么，我想要它做的。这是好的。

I have a C# Excel Add-in project "MyExcelAddIn" that has a public method Foo() to do something complex. For testing purposes, the add-in also defines a toolbar button which is wired to Foo() so I can test this and verify that clicking the button calls Foo() and does what I want it to do. This is fine.

现在我想调用从C＃Windows窗体项目中此方法。在Windows窗体项目，我可以创建一个Excel的实例，并使它可见，并确认我的VSTO加载运行，我可以看到按钮和它的作品。但是我不知道如何从Windows窗体项目调用foo（）编程。我GOOGLE了一下，得到尽可能获得MyExcelAddInCOMAddIn对象，但无法工作，如何调用foo（）。

Now I want to call this method from a C# Windows Forms project. In the Windows Forms project I can create an Excel instance and make it visible and verify that my VSTO add-in is running as I can see the button and it works. But I can't work out how to call Foo() programatically from the Windows Forms project. I've googled a bit and got as far as getting the "MyExcelAddIn" COMAddIn object, but can't work out how to call Foo().

这看起来是这样的：

// Create Excel and make it visible
Application excelApp = new Application();
excelApp.Visible = true;

// I know my VSTO add-in is running because I can see my test button
// Now get a reference to my VSTO add-in
Microsoft.Office.Core.COMAddIns comAddIns = _excelApp.COMAddIns;
object addinName = "MyExcelAddIn";
Microsoft.Office.Core.COMAddIn myAddin = comAddIns.Item(ref addinName);
// This works, but now what? How do I make a call on myAddin?
// Note that myAddin.Object is null...

所以，我想知道我能做些什么来调用foo（）从我的Windows窗体应用程序。请注意，我已经在Windows窗体应用程序和外接两种完全控制，我怀疑我必须做出改变，以他们两人（尤其是加载项），但我不知道如何做到这一点。

So I want to know what I can do to call Foo() from my Windows Forms application. Note that I have full control over both the Windows Forms application and the add-in and I suspect I have to make changes to both of them (particularly the add-in) but I have no idea how to do this.

请注意，这是一个VS2008 C＃应用程序，我用Excel 2003。

Note that this is a VS2008 C# application and I'm using Excel 2003.

推荐答案

我使用的是SendMessage函数的Win32 API来做到这一点。我的C＃外接一个潮头窗口标题的WinForm的应用程序可以找到创建一个的NativeWindow。

I'm using the SendMessage Win32 API to do this. My C# Add-in creates a "NativeWindow" with a uniqe window title that the WinForm app can locate.