导出excel 格式自己随意调整

           Microsoft.Office.Interop.Excel.Workbooks workbooks = xlApp.Workbooks;
            Microsoft.Office.Interop.Excel.Workbook workbook = workbooks.Add(Microsoft.Office.Interop.Excel.XlWBATemplate.xlWBATWorksheet);
            object missing = System.Reflection.Missing.Value;
            Microsoft.Office.Interop.Excel.Worksheet sheets = (Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets.Add(missing, missing, 1,
            Microsoft.Office.Interop.Excel.XlSheetType.xlWorksheet);

            Microsoft.Office.Interop.Excel.Worksheet worksheet1 = (Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets[1];//取得sheet1

           worksheet1.Name = "工作薄一";//工作薄命名

          worksheet1.Range["C1:F1"].Merge();//合并单元格

          worksheet1.Cells[1, 3] = "单元格填入内容";

            worksheet1.Range["A1:C1"].Select();
            worksheet1.Shapes.AddPicture（“filepath”）//在单元格中添加图片

                    workbook.Saved = true;
                    workbook.SaveCopyAs(savaFileName);//保存文件
                    fileSaved = true;