PRivate _Workbook _workBook = null;
        private Worksheet _workSheet = null;
        private Worksheet _workSheet2 = null;
        private Excel.application _excelApplicatin = null;
        private Excel.Chart _excelChart = null;

          _excelApplicatin = new Excel.Application();
          _excelApplicatin.Visible = true;
          _excelApplicatin.DisplayAlerts = true;
          _workBook = _excelApplicatin.Workbooks.Add(XlSheetType.xlWorksheet);
          _workSheet = (Worksheet)_workBook.ActiveSheet;
          _workSheet.Name = "多数边框线为实线";
          Excel.Range excelRange = _workSheet.get_Range(_workSheet.Cells[2, 2], _workSheet.Cells[6, 6]);
          ExcelBorderLineStlye(excelRange,"Up","Bottom"," Left" "Right");

         //excelRange :excel选中范围的边框线型设置   因为多数边框线为实线
        //NO :表示边框没有; "Up Bottom Left Right":表示线型为粗线 ;" "" "表示线型细线

        private void ExcelBorderLineStlye(Range excelRange, string Up, string Bottom, string Left, string Right)
        {
            List<string> borderWeightDivision = new List<string>();
            borderWeightDivision.Add(Up);
            borderWeightDivision.Add(Bottom);
            borderWeightDivision.Add(Left);
            borderWeightDivision.Add(Right);

            for (int i = 0; i < borderWeightDivision.Count; i++)
            {
                if (borderWeightDivision[i].Length > 0)
                {
                    if (!borderWeightDivision[i].Equals("NO"))
                    {
                        switch (i)
                        {
                            //Top
                            case 0:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeTop).Weight = XlBorderWeight.xlMedium;
                                break;
                            //Bottom
                            case 1:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeBottom).Weight = XlBorderWeight.xlMedium;
                                break;
                            //"Left"
                            case 2:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeLeft).Weight = XlBorderWeight.xlMedium;
                                break;
                            //"Right"
                            case 3:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeRight).Weight = XlBorderWeight.xlMedium;
                                break;
                        }
                    }
                    else
                    {
                        switch (i)
                        {
                            //Top
                            case 0:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeTop).LineStyle = XlLineStyle.xlLineStyleNone;
                                break;
                            //Bottom
                            case 1:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeBottom).LineStyle = XlLineStyle.xlLineStyleNone;
                                break;
                            //"Left"
                            case 2:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeLeft).LineStyle = XlLineStyle.xlLineStyleNone;
                                break;
                            //"Right"
                            case 3:
                                excelRange.Borders.get_Item(XlBordersIndex.xlEdgeRight).LineStyle = XlLineStyle .xlLineStyleNone;
                                break;
                        }
                    }
                }
                else
                {
                    switch (i)
                    {
                        //Top
                        case 0:
                            excelRange.Borders.get_Item(XlBordersIndex.xlEdgeTop).Weight = XlBorderWeight.xlThin;
                            break;
                        //Bottom
                        case 1:
                            excelRange.Borders.get_Item(XlBordersIndex.xlEdgeBottom).Weight = XlBorderWeight.xlThin;
                            break;
                        //"Left"
                        case 2:
                            excelRange.Borders.get_Item(XlBordersIndex.xlEdgeLeft).Weight = XlBorderWeight.xlThin;
                            break;
                        //"Right"
                        case 3:
                            excelRange.Borders.get_Item(XlBordersIndex.xlEdgeRight).Weight = XlBorderWeight.xlThin;
                            break;
                    }
                }
            }
        }