c# DataTable导出为excel

 /// <summary>
        /// 将DataTable导出为Excel文件(.xls) 
        /// </summary>
        /// <param name="dt">要导出的DataTable</param>
        public static void ExportToExcel(System.Data.DataTable dt)
        {
            if (dt == null) return;
            Microsoft.Office.Interop.Excel.Application xlApp = new Microsoft.Office.Interop.Excel.Application();
            if (xlApp == null)
            {
                MessageBox.Show("无法创建Excel对象，可能您的电脑未安装Excel");
                return;
            }

            System.Windows.Forms.SaveFileDialog saveDia = new SaveFileDialog();
            saveDia.Filter = "Excel|*.xls";
            saveDia.Title = "导出为Excel文件";

            if (saveDia.ShowDialog() == System.Windows.Forms.DialogResult.OK
             && !string.Empty.Equals(saveDia.FileName))
            {
                Microsoft.Office.Interop.Excel.Workbooks workbooks = xlApp.Workbooks;
                Microsoft.Office.Interop.Excel.Workbook workbook = workbooks.Add(Microsoft.Office.Interop.Excel.XlWBATemplate.xlWBATWorksheet);
                Microsoft.Office.Interop.Excel.Worksheet worksheet = (Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets[1];//取得sheet1
                Microsoft.Office.Interop.Excel.Range range = null;

                long totalCount = dt.Rows.Count;
                long rowRead = 0;
                float percent = 0;
                string fileName = saveDia.FileName;

                //写入标题
                for (int i = 0; i < dt.Columns.Count; i++)
                {
                    worksheet.Cells[1, i + 1] = dt.Columns[i].ColumnName;
                    range = (Microsoft.Office.Interop.Excel.Range)worksheet.Cells[1, i + 1];
                    //range.Interior.ColorIndex = 15;//背景颜色
                    range.Font.Bold = true;//粗体
                    range.HorizontalAlignment = Microsoft.Office.Interop.Excel.XlHAlign.xlHAlignCenter;//居中
                    //加边框
                    range.BorderAround(Microsoft.Office.Interop.Excel.XlLineStyle.xlContinuous, Microsoft.Office.Interop.Excel.XlBorderWeight.xlThin, Microsoft.Office.Interop.Excel.XlColorIndex.xlColorIndexAutomatic, null);

                    //range.ColumnWidth = 4.63;//设置列宽
                    //range.EntireColumn.AutoFit();//自动调整列宽
                    //r1.EntireRow.AutoFit();//自动调整行高
                }

                //写入内容

                for (int r = 0; r < dt.DefaultView.Count; r++)
                {                    
                    for (int i = 0; i < dt.Columns.Count; i++)
                    {
                        worksheet.Cells[r + 2, i + 1] = dt.DefaultView[r][i];
                        range = (Microsoft.Office.Interop.Excel.Range)worksheet.Cells[r + 2, i + 1];
                        range.Font.Size = 9;//字体大小
                        //加边框
                        range.BorderAround(Microsoft.Office.Interop.Excel.XlLineStyle.xlContinuous, Microsoft.Office.Interop.Excel.XlBorderWeight.xlThin, Microsoft.Office.Interop.Excel.XlColorIndex.xlColorIndexAutomatic, null);
                        range.EntireColumn.AutoFit();//自动调整列宽
                    }

                    rowRead++;
                    percent = ((float)(100 * rowRead)) / totalCount;
                    System.Windows.Forms.Application.DoEvents();
                }

                range.Borders[Microsoft.Office.Interop.Excel.XlBordersIndex.xlInsideHorizontal].Weight = Microsoft.Office.Interop.Excel.XlBorderWeight.xlThin;
                if (dt.Columns.Count > 1)
                {
                    range.Borders[Microsoft.Office.Interop.Excel.XlBordersIndex.xlInsideVertical].Weight = Microsoft.Office.Interop.Excel.XlBorderWeight.xlThin;
                }

                try
                {
                    workbook.Saved = true;
                    workbook.SaveCopyAs(fileName);
                }
                catch (Exception ex)
                {
                    MessageBox.Show("导出文件时出错,文件可能正被打开！\n" + ex.Message);
                    return;
                }

                workbooks.Close();
                if (xlApp != null)
                {
                    xlApp.Workbooks.Close();
                    xlApp.Quit();
                    int generation = System.GC.GetGeneration(xlApp);
                    System.Runtime.InteropServices.Marshal.ReleaseComObject(xlApp);
                    xlApp = null;
                    System.GC.Collect(generation);

                }

                GC.Collect();//强行销毁
                #region 强行杀死最近打开的Excel进程

                System.Diagnostics.Process[] excelProc = System.Diagnostics.Process.GetProcessesByName("EXCEL");
                System.DateTime startTime = new DateTime();
                int m, killId = 0;
                for (m = 0; m < excelProc.Length; m++)
                {
                    if (startTime < excelProc[m].StartTime)
                    {
                        startTime = excelProc[m].StartTime;
                        killId = m;
                    }
                }
                if (excelProc[killId].HasExited == false)
                {
                    excelProc[killId].Kill();
                }

                #endregion
                MessageBox.Show("导出成功!");
            }
        }