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

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1. object oMissing = System.Reflection.Missing.Value;  
2.                 Microsoft.Office.Interop.Excel.Application excelApp = new Microsoft.Office.Interop.Excel.Application();  
3.                 excelApp.UserControl = true;  
4.                 excelApp.DisplayAlerts = false;  
5.                 excelApp.Application.Workbooks.Open(strFilePath, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing, oMissing);  
6.                 Workbook workBook = excelApp.Workbooks[1];  
7.                 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?

[csharp] view plaincopy

1. 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