private Excel.Application m_app;
　　private Excel.Workbook m_workbook;
　　this.m_app = new Excel.ApplicationClass();
　　this.m_app.DisplayAlerts = false;
　　this.m_workbook = this.m_app.Workbooks.Open(sFilePath, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value );

　　private Excel.Application m_app;
　　private Excel.Workbooks m_workbooks;
　　private Excel.Workbook m_workbook;
　　this.m_app = new Excel.ApplicationClass();
　　this.m_app.DisplayAlerts = false;
　　m_workbooks = this.m_app.Workbooks;
　　this.m_workbook = this.m_workbooks.Open(sFilePath, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value, Missing.Value, Missing.Value,
　　Missing.Value );

　　Excel._Worksheet worksheet1 = null;
　　worksheet1 = (Excel._Worksheet) this.m_workbook.Worksheets.get_Item(sSheetName);
　　修改后如下：
　　Excel.Sheets sheets = null ;
　　Excel._Worksheet worksheet1 = null;
　　sheets = this.m_workbook.Worksheets;
　　worksheet1 = (Excel._Worksheet) sheets.get_Item(sSheetName);

　　private void ReleaseAllRef(Object obj)
　　{
　　try
　　{
　　if (obj != null )
　　{
　　while (Marshal.ReleaseComObject(obj) > 1);
　　}
　　}
　　finally
　　{
　　obj = null;
　　}
　　}
　　private void Release()
　　{
　　if (m_app != null )
　　{
　　m_app.Quit() ;
　　}
　　ReleaseAllRef(m_workbook) ;
　　m_workbook = null ;
　　ReleaseAllRef(m_workbooks) ;
　　m_workbooks = null ;
　　ReleaseAllRef(m_app) ;
　　m_app = null ;
　　System.GC.Collect() ;
　　}