Error    1    The type or namespace name 'Excel' could not be found (are you missing a using directive or an assembly reference?)    C:\Documents and Settings\Administrator\My Documents\Visual Studio 2008\Projects\Project1\WindowsFormsApplication1\WindowsFormsApplication1\Form1.cs    10    7    WindowsFormsApplication1

using Excel = Microsoft.Office.Interop.Excel;
我自己解决了

恩，要添加OFFICE控件。