先上导出代码  
    /// <summary>  
            /// 导出速度最快  
            /// </summary>  
            /// <param name="list"><列名，数据></param>  
            /// <param name="filepath"></param>  
            /// <returns></returns>  
            public bool NewExport(List<DictionaryEntry> list, string filepath)  
            {  
                bool bSuccess = true;  
                Microsoft.Office.Interop.Excel.Application appexcel = new Microsoft.Office.Interop.Excel.Application();  
                System.Reflection.Missing miss = System.Reflection.Missing.Value;  
                appexcel = new Microsoft.Office.Interop.Excel.Application();  
                Microsoft.Office.Interop.Excel.Workbook workbookdata = null;  
                Microsoft.Office.Interop.Excel.Worksheet worksheetdata = null;  
                Microsoft.Office.Interop.Excel.Range rangedata;  
      
                workbookdata = appexcel.Workbooks.Add();  
      
                //设置对象不可见  
                appexcel.Visible = false;  
                appexcel.DisplayAlerts = false;  
                try  
                {  
                    foreach (var lv in list)  
                    {  
                        var keys = lv.Key as List<string>;  
                        var values = lv.Value as List<IList<object>>;  
                        worksheetdata = (Microsoft.Office.Interop.Excel.Worksheet)workbookdata.Worksheets.Add(miss, workbookdata.ActiveSheet);  
      
                        for (int i = 0; i < keys.Count-1; i++)  
                        {  
                            //给工作表赋名称  
                            worksheetdata.Name = keys[0];//列名的第一个数据位表名  
                            worksheetdata.Cells[1, i + 1] = keys[i+1];  
                        }  
      
                        //因为第一行已经写了表头，所以所有数据都应该从a2开始  
                        rangedata = worksheetdata.get_Range("a2", miss);  
                        Microsoft.Office.Interop.Excel.Range xlrang = null;  
      
                        //irowcount为实际行数，最大行  
                        int irowcount = values.Count;  
                        int iparstedrow = 0, icurrsize = 0;  
      
                        //ieachsize为每次写行的数值，可以自己设置  
                        int ieachsize = 10000;  
      
                        //icolumnaccount为实际列数，最大列数  
                        int icolumnaccount = keys.Count-1;  
      
                        //在内存中声明一个ieachsize×icolumnaccount的数组，ieachsize是每次最大存储的行数，icolumnaccount就是存储的实际列数  
                        object[,] objval = new object[ieachsize, icolumnaccount];  
                        icurrsize = ieachsize;  
      
                        while (iparstedrow < irowcount)  
                        {  
                            if ((irowcount - iparstedrow) < ieachsize)  
                                icurrsize = irowcount - iparstedrow;  
      
                            //用for循环给数组赋值  
                            for (int i = 0; i < icurrsize; i++)  
                            {  
                                for (int j = 0; j < icolumnaccount; j++)  
                                {  
                                    var v = values[i + iparstedrow][j];  
                                    objval[i, j] = v != null ? v.ToString() : "";  
                                }  
                            }  
                            string X = "A" + ((int)(iparstedrow + 2)).ToString();  
                            string col = "";  
                            if (icolumnaccount <= 26)  
                            {  
                                col = ((char)('A' + icolumnaccount - 1)).ToString() + ((int)(iparstedrow + icurrsize + 1)).ToString();  
                            }  
                            else  
                            {  
                                col = ((char)('A' + (icolumnaccount / 26 - 1))).ToString() + ((char)('A' + (icolumnaccount % 26 - 1))).ToString() + ((int)(iparstedrow + icurrsize + 1)).ToString();  
                            }  
                            xlrang = worksheetdata.get_Range(X, col);  
                            xlrang.NumberFormat = "@";  
                            // 调用range的value2属性，把内存中的值赋给excel  
                            xlrang.Value2 = objval;  
                            iparstedrow = iparstedrow + icurrsize;  
                        }  
                    }  
                    ((Microsoft.Office.Interop.Excel.Worksheet)workbookdata.Worksheets["Sheet1"]).Delete();  
                    ((Microsoft.Office.Interop.Excel.Worksheet)workbookdata.Worksheets["Sheet2"]).Delete();  
                    ((Microsoft.Office.Interop.Excel.Worksheet)workbookdata.Worksheets["Sheet3"]).Delete();  
                    //保存工作表  
                    workbookdata.SaveAs(filepath, miss, miss, miss, miss, miss, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, miss, miss, miss);  
                    workbookdata.Close(false, miss, miss);  
                    appexcel.Workbooks.Close();  
                    appexcel.Quit();  
      
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(workbookdata);  
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(appexcel.Workbooks);  
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(appexcel);  
                    GC.Collect();  
                }  
                catch (Exception ex)  
                {  
                    ErrorMsg = ex.Message;  
                    bSuccess = false;  
                }  
                finally  
                {  
                    if (appexcel != null)  
                    {  
                        ExcelImportHelper.KillSpecialExcel(appexcel);  
                    }  
                }  
                return bSuccess;  
            }