从单元格公式调用Excel 2007中用C＃编写的方法

I am using Excel 2007. I have C# code written in a separate binary. The code uses static classes and static methods on the classes. I have a reference to the DLL in my VSTO Excel Worksheet project. What do I have to add or modify to get this to work?I am using Excel 2007. I have C# code written i