DataTable数据导出到Excel,并发送到客户端进行下载

本代码实现思路是:页面显示和导出分开,导出的数据和用于页面显示的是同一查询数据方式,所以也是同样的数据,只是在导出数据时从数据库重新捞了一次数据。
此导出数据方式会先将数据保存到Excel中,然后将创建的Excel文件保存到服务器指定位置,然后下载到客户端,下载完后立即删除掉刚在服务器上创建的Excel文件。
 
// 导出按钮事件
protected void btOutputData_Click(object sender, EventArgs e)
    {
        ExportExcel(GetPrintingData(ViewState["ssearchCondition"].ToString()), Convert.ToInt32(ConfigurationManager.AppSettings["OutputData        PageSize"].ToString()));
    }


#region
导出数据 /// <summary> /// 获取需要导出的数据 /// </summary> /// <param name="strWhere">筛选数据的条件</param> /// <returns></returns> public System.Data.DataTable GetPrintingData(string strWhere) { System.Data.DataTable dt = GetListByPage(strWhere, 0, GetRecordCount(ViewState["ssearchCondition"].ToString())); System.Data.DataTable newTable = new System.Data.DataTable(); newTable.Columns.AddRange(new DataColumn[]{ new DataColumn("rowN"), new DataColumn("Description"), new DataColumn("area"), new DataColumn("projectName"), new DataColumn("stake"), new DataColumn("itemProjectName"), new DataColumn("newCol2"), new DataColumn("newCol3"), new DataColumn("newCol4"), new DataColumn("newCol5"), new DataColumn("newCol6"), new DataColumn("newCol7"), new DataColumn("acceptConclution_zdb"), new DataColumn("newCol8"), new DataColumn("acceptConclution_zjb"), new DataColumn("joinAccept_yz"), new DataColumn("joinAccept_zjb"), new DataColumn("joinAccept_zdb"), new DataColumn("joinAccept_xmb")}); int num = 1; for (int i = 0; i < dt.Rows.Count; i++) { DataRow newRow = newTable.NewRow(); newRow["rowN"] = num++;// dt.Rows[i]["rowN"]; newRow["Description"] = dt.Rows[i]["Description"]; newRow["area"] = dt.Rows[i]["area"]; newRow["projectName"] = dt.Rows[i]["projectName"]; newRow["stake"] = dt.Rows[i]["stake"]; newRow["itemProjectName"] = dt.Rows[i]["itemProjectName"]; newRow["newCol2"] = dt.Rows[i]["newCol2"]; newRow["newCol3"] = dt.Rows[i]["newCol3"]; newRow["newCol4"] = dt.Rows[i]["newCol4"]; newRow["newCol5"] = dt.Rows[i]["newCol5"]; newRow["newCol6"] = dt.Rows[i]["newCol6"]; newRow["newCol7"] = dt.Rows[i]["newCol7"]; newRow["acceptConclution_zdb"] = dt.Rows[i]["acceptConclution_zdb"]; newRow["newCol8"] = dt.Rows[i]["newCol8"]; newRow["acceptConclution_zjb"] = dt.Rows[i]["acceptConclution_zjb"]; newRow["joinAccept_yz"] = dt.Rows[i]["joinAccept_yz"]; newRow["joinAccept_zjb"] = dt.Rows[i]["joinAccept_zjb"]; newRow["joinAccept_zdb"] = dt.Rows[i]["joinAccept_zdb"]; newRow["joinAccept_xmb"] = dt.Rows[i]["joinAccept_xmb"]; newTable.Rows.Add(newRow); } return newTable; } /// <summary> /// 把table中的数据导出到excel中去 /// </summary> /// <param name="dt">要导入的table</param> /// <param name="maxcount">模板excel中,一个sheet要显示的行数,如果数据多一个sheet中的最大值,会自动生成新的sheet</param> private void ExportExcel(System.Data.DataTable dt, int maxcount) { Random ran = new Random(); string fileautoname = Server.MapPath("~/") + DateTime.Now.ToString("yyyyMMddhhmmss") + ran.Next(100, 999) + ".xls";//给新文件命名 string filepath = Server.MapPath("/") + "UpLoadFile\Template\OutputDataBlock.xls"; //模板文件路径 object missing = Type.Missing; Microsoft.Office.Interop.Excel.Application application = new Application(); Workbook workbook = application.Workbooks.Open(filepath, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing, missing); Worksheet worksheet; worksheet = (Worksheet)workbook.Sheets.get_Item(1); //DataView dv = dt.DefaultView; //dv.Sort = "id asc"; //table 中的数据按id升序排列 //System.Data.DataTable table = dv.ToTable(); System.Data.DataTable table = dt; int sheetcount = GetSheetCount(table.Rows.Count, maxcount); for (int count = 1; count < sheetcount; count++) { ((Microsoft.Office.Interop.Excel.Worksheet)workbook.Worksheets.get_Item(count)).Copy(missing, workbook.Worksheets[count]); } List<object[,]> list = new List<object[,]>(); object[,] ret; for (int count = 0; count < sheetcount; count++) { if (count == sheetcount - 1) { ret = new object[table.Rows.Count - count * maxcount, table.Columns.Count - 2]; for (int i = 0; i < table.Rows.Count - count * maxcount; i++) { for (int j = 0; j < table.Columns.Count - 2; j++) { ret[i, j] = table.Rows[count * maxcount + i][j]; } } list.Add(ret); } else { ret = new object[maxcount, table.Columns.Count - 2]; for (int i = 0; i < maxcount; i++) { for (int j = 0; j < table.Columns.Count - 2; j++) { ret[i, j] = table.Rows[i + count * maxcount][j]; } } list.Add(ret); } } object[,] obj; for (int p = 0; p < list.Count; p++) { worksheet = (Worksheet)workbook.Sheets.get_Item(p + 1); obj = list[p]; string cn = "L" + (obj.GetLength(0) + 2).ToString(); //设置填充区域 worksheet.get_Range("A3", cn).FormulaR1C1 = obj; } workbook.SaveAs(fileautoname, missing, missing, missing, missing, missing, Microsoft.Office.Interop.Excel.XlSaveAsAccessMode.xlNoChange, missing, missing, missing, missing, missing); workbook.Close(missing, missing, missing); application.Quit(); workbook = null; #region System.IO.FileInfo file = new System.IO.FileInfo(fileautoname); Response.Clear(); Response.Charset = "GB2312"; Response.ContentEncoding = System.Text.Encoding.UTF8; // 添加头信息,为"文件下载/另存为"对话框指定默认文件名 Response.AddHeader("Content-Disposition", "attachment; filename=" + Server.UrlEncode(file.Name)); // 添加头信息,指定文件大小,让浏览器能够显示下载进度 Response.AddHeader("Content-Length", file.Length.ToString()); // 指定返回的是一个不能被客户端读取的流,必须被下载 Response.ContentType = "application/ms-excel"; // 把文件流发送到客户端 Response.WriteFile(file.FullName); Response.Flush();//这个语句必须有,否则就不回弹出保存的对话框,搞了N久 //删除长生的临时Excel文件 string filePath = fileautoname;//获取文件路径 if (filePath != null && System.IO.File.Exists(filepath)) { //判断文件是否存在,如果存在,就删除之 System.IO.File.Delete(filePath); } // 停止页面的执行 Response.End(); #endregion } /// <summary> /// 获取WorkSheet数量 /// </summary> /// <param name="rowCount">记录总行数</param> /// <param name="rows">每WorkSheet行数</param> /// <returns></returns> private int GetSheetCount(int rowCount, int rows) { int n = rowCount % rows; //余数 if (n == 0) return rowCount / rows; else return Convert.ToInt32(rowCount / rows) + 1; } #endregion
原文地址:https://www.cnblogs.com/stevenjson/p/3147173.html