ASP.NET之Excel下载模板、导入、导出操作

1.下载模板功能

　　前提是服务器某文件夹中有这个文件。代码如下

protected void btnDownload_Click(object sender, EventArgs e)
{
    var path = Server.MapPath(("upfiles\") + "test.xlt");      //upfiles-文件夹 test.xlt-文件
    var name = "test.xlt";

    try
    {
        var file = new FileInfo(path);
        Response.Clear();
        Response.Charset = "GB2312";
        Response.ContentEncoding = System.Text.Encoding.UTF8;
        Response.AddHeader("Content-Disposition", "attachment; filename=" + Server.UrlEncode(name)); //头信息，指定默认文件名
        Response.AddHeader("Content-Length", file.Length.ToString());//显示下载进度
        Response.ContentType = "application/ms-excel";     // 指定返回的是一个不能被客户端读取的流，必须被下载
        Response.WriteFile(file.FullName);    // 把文件流发送到客户端
            
        HttpContext.Current.ApplicationInstance.CompleteRequest();
    }
    catch (Exception ex)
    {
        Response.Write("<script>alert('错误:" + ex.Message + ",请尽快与管理员联系')</script>");
    }
}

2.导入数据

　　Excel数据导入到数据库中。

protected void btnImport_Click(object sender, EventArgs e)
{
    if (FileUpload1.HasFile == false)   //判断是否包含一个文件
    {
        Response.Write("<script>alert('请您选择Excel文件！')</script>");//未上传就点击了导入按钮
        return;
    }
    string isXls = Path.GetExtension(FileUpload1.FileName).ToString().ToLower();//获得文件的扩展名
    var extenLen = isXls.Length;

    if (!isXls.Contains(".xls"))    //判断是否 是excel文件
    {
        Response.Write("<script>alert('只可以选择Excel文件！')</script>");
        return;
    }

    string filename = FileUpload1.FileName;              //获取Excle文件名
    string savePath = Server.MapPath(("upfiles\") + filename);//Server.MapPath 获得虚拟服务器相对路径
    string savePath2 = Server.MapPath(("upfiles\"));

    if (!Directory.Exists(savePath2))   //如果不存在upfiles文件夹则创建
    {
        Directory.CreateDirectory(savePath2);
    }
    FileUpload1.SaveAs(savePath);  //SaveAs 将上传的文件内容保存在服务器上
    var ds = ExcelSqlConnection(savePath, filename);           //将Excel转成DataSet
    var dtRows = ds.Tables[0].Rows.Count;
    var dt = ds.Tables[0];
    if (dtRows == 0)
    {
        Response.Write("<script>alert('Excel表无数据！')</script>");
        return;
    }
    try
    {
        for(int i = 0; i < dt.Rows.Count; i++)
        {
            string ve = dt.Rows[i]["车号"].ToString();
            if (string.IsNullOrEmpty(ve))   //因数据库中车号不能为空 所以表格中车号为空的跳过这行
            {
                continue;
            }
            //用自己的方式保存进数据库ADO/EF/...
            var model = new TEST(); //实体
            model.id = 1;
            model.ve = ve;
            model.name = dt.Rows[i]["姓名"].ToString();
            model.Update();
        }
    }catch (Exception ex)
    {
        Response.Write("<script>alert('" + ex.Message + "')</script>");   
    }
    
}

private DataSet ExcelSqlConnection(string savePath, string tableName)
{
    //string strCon = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + savePath + ";Extended Properties='Excel 8.0;HDR=YES;IMEX=1'";
    string strCon = "Provider=Microsoft.Ace.OLEDB.12.0;" + "data source=" + savePath + ";Extended Properties='Excel 12.0; HDR=Yes; IMEX=1'";    //HDR=YES Excel文件的第一行是列名而不是数据 IMEX=1可必免数据类型冲突
    var excelConn = new OleDbConnection(strCon);
    try
    {
        string strCom = string.Format("SELECT * FROM [Sheet1$]");
        excelConn.Open();
        OleDbDataAdapter myCommand = new OleDbDataAdapter(strCom, excelConn);
        DataSet ds = new DataSet();
        myCommand.Fill(ds, "[" + tableName + "$]");
        excelConn.Close();
        return ds;
    }
    catch (Exception)
    {
        excelConn.Close();
        //Response.Write("<script>alert('" + ex.Message + "')</script>");
        return null;
    }

}

3.导出数据到Excel中

插件采用MyXLS.
以下代码大部分基本不用改。

private void Export()
{
    XlsDocument xls = new XlsDocument();
    org.in2bits.MyXls.Cell cell;
    int rowIndex = 2;

    xls.FileName = DateTime.Now.ToString().Replace("-", "").Replace(":", "").Replace(" ", "") + HttpUtility.UrlEncode("TEST") + ".xls"; //TEST要改
    Worksheet sheet = xls.Workbook.Worksheets.AddNamed("TEST");//状态栏标题名称
    org.in2bits.MyXls.Cells cells = sheet.Cells;

    #region 导出Excel列宽
    ColumnInfo colInfo = new ColumnInfo(xls, sheet);
    colInfo.ColumnIndexStart = 0;
    colInfo.ColumnIndexEnd = 2;     
    colInfo.Width = 15 * 300;
    sheet.AddColumnInfo(colInfo);
    #endregion

    #region 表头
    MergeArea area = new MergeArea(1, 1, 1, 2); //MergeArea(int rowMin, int rowMax, int colMin, int colMax)
    org.in2bits.MyXls.Cell cellTitle = cells.AddValueCell(1, 1, "TEST");    //Excel 第一行第1到2列显示TEST
    sheet.AddMergeArea(area);
    cellTitle.Font.Height = 20 * 20;
    cellTitle.Font.Bold = true;//设置标题行的字体为粗体
    cellTitle.Font.FontFamily = FontFamilies.Roman;//设置标题行的字体为FontFamilies.Roman
    cellTitle.HorizontalAlignment = HorizontalAlignments.Centered;

    area = new MergeArea(2, 2, 1, 1);
    cellTitle = cells.AddValueCell(2, 1, "车号"); //第二行第一列 显示车号
    sheet.AddMergeArea(area);
    cellTitle.Font.Bold = true;
    cellTitle.Font.Height = 16 * 16;
    cellTitle.Font.FontFamily = FontFamilies.Roman;
    cellTitle.HorizontalAlignment = HorizontalAlignments.Centered;
    cellTitle.VerticalAlignment = VerticalAlignments.Centered;
    cellTitle.TopLineStyle = 1;
    cellTitle.BottomLineStyle = 1;
    cellTitle.LeftLineStyle = 1;
    cellTitle.RightLineStyle = 1;

    area = new MergeArea(2, 2, 2, 2);
    cellTitle = cells.AddValueCell(2, 2, "姓名");
    sheet.AddMergeArea(area);
    cellTitle.Font.Bold = true;
    cellTitle.Font.Height = 16 * 16;
    cellTitle.Font.FontFamily = FontFamilies.Roman;
    cellTitle.HorizontalAlignment = HorizontalAlignments.Centered;
    cellTitle.VerticalAlignment = VerticalAlignments.Centered;
    cellTitle.TopLineStyle = 1;
    cellTitle.BottomLineStyle = 1;
    cellTitle.LeftLineStyle = 1;
    cellTitle.RightLineStyle = 1;

    #endregion

    var list = GetList();  //获取数据

    for (int i = 0; i < list.Count; i++)
    {
        rowIndex++;
        cell = cells.AddValueCell(rowIndex, 1, list[i].VehicleNO);  //车号
        cell.TopLineStyle = 1;
        cell.BottomLineStyle = 1;
        cell.LeftLineStyle = 1;
        cell.RightLineStyle = 1;

        cell = cells.AddValueCell(rowIndex, 2, list[i].Name);   //姓名
        cell.TopLineStyle = 1;
        cell.BottomLineStyle = 1;
        cell.LeftLineStyle = 1;
        cell.RightLineStyle = 1;

    }
    xls.Send();
}

4.错误-未在本地计算机上注册“Microsoft.ACE.OLEDB.12.0”提供程序

　　01.将平台换成X86

　　02.安装 AccessDatabaseEngine.exe(点击下载)

5.错误-服务器无法在发送HTTP标头之后设置内容类型

　　给导出按钮增加'全局刷新'的能力。本文例子是aspx做的

　在<asp:UpdatePanel> 标签中 增加如下代码即可

<Triggers>
    <%--<asp:AsyncPostBackTrigger ControlID="" />--%> <%--局部刷新 值刷新UpdatePanel内部 --%>
    <asp:PostBackTrigger ControlID="btnExport" /> <%--全部刷新 --%> <%--2016年7月1日 解决点击导出按钮报错“服务器无法在发送HTTP标头之后设置内容类型”的错误--%>
</Triggers>