Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: “object”未包含“get_Range”的定义

asp.net操作Excel合并单元格时，抛出了异常：

Microsoft.CSharp.RuntimeBinder.RuntimeBinderException: “object”未包含“get_Range”的定义
在 CallSite.Target(Closure , CallSite , ComObject , Object , Object )
在 System.Dynamic.UpdateDelegates.UpdateAndExecute3[T0,T1,T2,TRet](CallSite site, T0 arg0, T1 arg1, T2 arg2)
在 CallSite.Target(Closure , CallSite , Application , Object , Object )
在 System.Dynamic.UpdateDelegates.UpdateAndExecute3[T0,T1,T2,TRet](CallSite site, T0 arg0, T1 arg1, T2 arg2)

开发环境：VS2010+Framework4.0+Microsoft.Office.Interop.Excel 11.0

解决方案：

2.0 worksheet.get_Range(worksheet.Cells[1, 1], worksheet.Cells[1, 3]).Merge(mValue);

4.0 Microsoft.Office.Interop.Excel.Range range = worksheet.Range[worksheet.Cells[1, i + 1], worksheet.Cells[2, i + 1]];

range.MergeCells = true;