C# 调用Excel报 error CS1969: 找不到编译动态表达式所需的一个或多个类型。是否缺少引用?

程序需要读取Exel文件，有如下代码段

 object oMissing = System.Reflection.Missing.Value;
                 Microsoft.Office.Interop.Excel.Application excelApp = new Microsoft.Office.Interop.Excel.Application();
                 excelApp.UserControl = true;
                 excelApp.DisplayAlerts = false;
                 excelApp.Application.Workbooks.Open(strFilePath, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing);
                 Workbook workBook = excelApp.Workbooks[1];
                 Worksheet workSheet = (Worksheet)workBook.Worksheets[1];

下面这句话之前的.net2.0上没问题，在.net4.0上报错  error CS1969: 找不到编译动态表达式所需的一个或多个类型。是否缺少引用?

 Worksheet workSheet = (Worksheet)workBook.Worksheets[1];

解决方案：修改引用（Microsoft.Office.Interop.Excel）的属性“嵌入互操作类型”由True改为False即可