使用Microsoft.Office.Interop.Excel和SteamWriter的方式导出Excel

之前在另外一篇博文里面介绍了使用NPOI的方式导入导出Excel

其实asp.net提供了相应的dll给我们操作Excel

1.引用Microsoft.Office.Interop.Excel.dll

通过这个dll也是可以导出Excel的，不过这种方式写起来很麻烦，代码参考如下

/// <summary>
        /// 使用Microsoft.Office.Interop.Excel导出
        /// </summary>
        /// <param name="dt"></param>
        public static void DataTableToExcel(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|*.xlsx";
            saveDia.Title = "导出为Excel文件";
            saveDia.FileName = DateTime.Now.ToString("yyyyMMddHHmmss");

            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.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);
                }

                //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！
" + 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
            }
        }

2.直接把内容通过SteamWriter字节流写入到Excel

这种方式我在本地测试是支持xls的，但是xlsx方式会打不开文件，代码参考如下

        /// <summary>
        /// 使用SteamWriter导出
        /// </summary>
        /// <param name="dt"></param>
        /// <param name="path"></param>
        public static void ExportDataTableToExcel(DataTable dt, string path)
        {
            KillSpecialExcel();
            try
            {
                // 实例化流对象，以特定的编码向流中写入字符。  
                StreamWriter sw = new StreamWriter(path, false, Encoding.UTF8);
                StringBuilder sb = new StringBuilder();
                for (int k = 0; k < dt.Columns.Count; k++)
                {
                    // 添加列名称  
                    sb.Append(dt.Columns[k].ColumnName.ToString() + "	");
                }
                sb.Append(Environment.NewLine);
                // 添加行数据  
                for (int i = 0; i < dt.Rows.Count; i++)
                {
                    DataRow row = dt.Rows[i];
                    for (int j = 0; j < dt.Columns.Count; j++)
                    {
                        // 根据列数追加行数据  
                        sb.Append(row[j].ToString() + "	");
                    }
                    sb.Append(Environment.NewLine);
                }
                sw.Write(sb.ToString());
                sw.Flush();
                sw.Close();
                sw.Dispose();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally
            {
                dt.Dispose();
            }
        }

        /// <summary>  
        /// 结束进程  
        /// </summary>  
        private static void KillSpecialExcel()
        {
            foreach (System.Diagnostics.Process theProc in System.Diagnostics.Process.GetProcessesByName("EXCEL"))
            {
                if (!theProc.HasExited)
                {
                    bool b = theProc.CloseMainWindow();
                    if (b == false)
                    {
                        theProc.Kill();
                    }
                    theProc.Close();
                }
            }
        }    

以上两种方式都可以，但是都不建议使用，通过NPOI这种第三方插件是最快的，也最方便