.net 代码实现文件下载

 

如果下载时直接通过访问文件的路径的方法，在下载.txt等文件时，浏览器会默认打开文件, 通过下面的方法，就可以避免浏览器打开文件，直接提示保存文件：

 

    /// <summary>
    /// 文件下载
    /// </summary>
    /// <param name="savename">保存时的文件名</param>
    /// <param name="FullFileName">下载文件路径   Server.Mappath(filepath)</param>
    /// <param name="Response">Response</param>
    public static void savefile(string savename, string FullFileName, System.Web.HttpResponse Response)
    {
        try
        {
            FileInfo DownloadFile = new FileInfo(FullFileName);
            if (DownloadFile.Exists)
            {
                Response.Clear();
                Response.ClearHeaders();
                Response.Buffer = false;
                Response.ContentType = "application/octet-stream";
                Response.AppendHeader("Content-Disposition", "p_w_upload;filename=" + System.Web.HttpUtility.UrlEncode(savename, System.Text.Encoding.UTF8));
                Response.AppendHeader("Content-Length", DownloadFile.Length.ToString());
                Response.TransmitFile(DownloadFile.FullName);
                Response.Flush();
                Response.End();
            }
            else
            {
                //文件不存在
            }
        }
        catch
        {
            //文件不存在
        }
    }