ASP.NET做一个下载程序

Question

现在想做一个下载的程序，当点击下载之后。把数据库里面的相应的字段填充到一个Excel文件里面，然后在吧Excel下载下来，请问问各位，这个应该怎么来做。谢谢了，一定给个实例。两三句话是说不清楚的，我是菜鸟，再次谢谢

Answer 1

这个涉及到有几个技术点
一个是数据的导出，一个是文件的下载。
1：首先在目录生成一个XLS文件（完成导出的操作）
2：再下载生成的XLS文件把思路理清，然后就去找相关的代码吧。

Answer 2

要代码前先自己把思路和需求理清。先读数据库生成相应的DATATABLE，然后DATATABLE导出EXCEL文件并下载。//dtData是要导出为Excel的DataTable,FileName是要导出的Excel文件名(不加.xls)
    public static void DataTable2Excel(System.Data.DataTable dtData, String FileName)
    {
        System.Web.UI.WebControls.GridView dgExport = null;
        //当前对话 
        System.Web.HttpContext curContext = System.Web.HttpContext.Current;
        //IO用于导出并返回excel文件 
        System.IO.StringWriter strWriter = null;
        System.Web.UI.HtmlTextWriter htmlWriter = null;        if (dtData != null)
        {
            //设置编码和附件格式 
            //System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8)作用是方式中文文件名乱码
            curContext.Response.AddHeader("content-disposition", "attachment;filename=" + System.Web.HttpUtility.UrlEncode(FileName, System.Text.Encoding.UTF8) + ".xls");
            curContext.Response.ContentType = "application/vnd.ms-excel";
            curContext.Response.ContentEncoding = System.Text.Encoding.UTF8;
            curContext.Response.Charset = "GB2312";            //导出Excel文件 
            strWriter = new System.IO.StringWriter();
            htmlWriter = new System.Web.UI.HtmlTextWriter(strWriter);            //为了解决dgData中可能进行了分页的情况,需要重新定义一个无分页的GridView 
            dgExport = new System.Web.UI.WebControls.GridView();
            dgExport.DataSource = dtData.DefaultView;
            dgExport.AllowPaging = false;
            //如果需要设置Excel格式,需要加入下面一行代码,同时添加dgExport_RowDataBound事件
            dgExport.RowDataBound += new GridViewRowEventHandler(dgExport_RowDataBound);
            dgExport.DataBind();            //下载到客户端 
            dgExport.RenderControl(htmlWriter);
            curContext.Response.Write(strWriter.ToString());
            curContext.Response.End();
        }
    }

Answer 3

先获取数据再创建excel或读取excel模板填充值
public void INSERT_Excel(DataView dvs,string strPath,string Name)
{
string s="";
Excel.Application app=new Application();
Excel._Workbook book;
Excel._Worksheet sheet;
book=(Excel._Workbook)app.Workbooks.Open(strPath,Missing.Value,Missing.Value,Missing.Value,Missing.Value,Missing.Value,Missing.Value,
Missing.Value,Missing.Value,Missing.Value,Missing.Value,Missing.Value,Missing.Value);
sheet=(Excel._Worksheet)book.Sheets[1];
int j=dvs.Count;
Excel.Range ran1=app.ActiveCell;
ran1=sheet.get_Range(sheet.Cells[1,1],sheet.Cells[1,9]);
ran1.Value2=Name;
for(int i=0;i<dvs.Count;i++)
{
try
{
s=Convert.ToString(i);
sheet.Cells[i+4,"A"]=dvs[i]["ID"].ToString().Trim();
}
catch(Exception ex)
{
HttpContext.Current.Response.Write("<script language='javascript'>alert('"+ex.Message+"')</script>");
book.Close(null,null,null);
app.Workbooks.Close();
app.Quit();
System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
System.Runtime.InteropServices.Marshal.ReleaseComObject(book);
System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
sheet=null;
book=null;
app=null;
GC.Collect();
HttpContext.Current.Response.Write("<script language='javascript'>alert('导出失败！')</script>");
return;
}
  
} 
book.Save();
book.Close(null,null,null);
app.Workbooks.Close();
app.Quit();
System.Runtime.InteropServices.Marshal.ReleaseComObject(app);
System.Runtime.InteropServices.Marshal.ReleaseComObject(book);
System.Runtime.InteropServices.Marshal.ReleaseComObject(sheet);
sheet=null;
book=null;
app=null;
GC.Collect();
GC.Collect();
GC.Collect();
HttpContext.Current.Response.Write("<script language='javascript'>alert('导出成功！')</script>");
HttpContext.Current.Response.Write("<script language='javascript'>window.open('../Template_temp/A.xls','_bank')</script>");
}

Answer 4

public string ExcelCache
        {
            get
            {
                string _path = Path.Combine(System.Web.Hosting.HostingEnvironment.ApplicationPhysicalPath, "ExcelBuffer\\");
                if (!Directory.Exists(_path))
                {
                    Directory.CreateDirectory(_path);
                }
                return _path;
            }        }                Report rpt = Report.LoadReport(Convert.ToInt32(reportID));
                ExcelHeaderBuilder builder = new ExcelHeaderBuilder();
                ExcelWorkbook book = new ExcelWorkbook();
                book.CreateSheet(sheetName);
                book.SetActiveSheet = sheetName;
                ExcelWorksheet sheet = book.GetSheet(sheetName);
                ExcelCellStyle style = book.CreateStyle();
                style.BorderColour = EnumColours.Black;
                style.BorderLineStyle = EnumLineStyle.Thin;
                style.Font.Name = "黑体";
                style.Font.Size = 12;
                style.HorizontalAlignment = EnumHorizontalAlignment.Center;
                style.VerticalAlignment = EnumVerticalAlignment.Center;                builder.Style = style;
                builder.MakeHeader(sheet, rpt);                book.Save(path);
                    HttpContext.Current.Response.Clear();
                    HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=" + Path.GetFileName(path));
                    HttpContext.Current.Response.ContentType = "application/octet-stream";
                    HttpContext.Current.Response.Charset = "GB2312";
                    HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.GetEncoding("GB2312");
                    HttpContext.Current.Response.WriteFile(path);
                    HttpContext.Current.Response.Flush();参考