if(File1.PostedFile.ContentLength>0)
如果用户有上传的文件，则：
string name = File1.PostedFile.FileName ;//获取输入的文件名字
int i= name.LastIndexOf(".") ;
string newname =name.Substring(i) ;//获取文件的扩展名
//改变下面的“c:\"到你想要保存的地址。
DateTime now=DateTime.Now;
string strname=now.Year.ToString()+now.Month.ToString()+now.Day.ToString()+File1.PostedFile.ContentLength.ToString()+newname;//对文件进行重命名。名字为：年+月+日+文件大小。
asp.net下载文件的常用方法大全(转)
1.流方式下载 protected void Button4_Click(object sender, EventArgs e) { string fileName = "aaa.txt";//客户端保存的文件名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路径
//以字符流的形式下载文件 FileStream fs = new FileStream(filePath, FileMode.Open); byte[] bytes = new byte[(int)fs.Length]; fs.Read(bytes, 0, bytes.Length); fs.Close(); Response.ContentType = "application/octet-stream"; //通知浏览器下载文件而不是打开 Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)); Response.BinaryWrite(bytes); Response.Flush(); Response.End();
}
2.WriteFile分块下载 protected void Button3_Click(object sender, EventArgs e) {
string fileName = "aaa.txt";//客户端保存的文件名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路径
System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath);
if (fileInfo.Exists == true) { const long ChunkSize = 102400;//100K 每次读取文件，只读取100Ｋ，这样可以缓解服务器的压力 byte[] buffer = new byte[ChunkSize];
Response.Clear(); System.IO.FileStream iStream = System.IO.File.OpenRead(filePath); long dataLengthToRead = iStream.Length;//获取下载的文件总大小 Response.ContentType = "application/octet-stream"; Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName)); while (dataLengthToRead > 0 && Response.IsClientConnected) { int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小 Response.OutputStream.Write(buffer, 0, lengthRead); Response.Flush(); dataLengthToRead = dataLengthToRead - lengthRead; } Response.Close(); } }
3.WriteFile实现下载 protected void Button2_Click(object sender, EventArgs e) { /* using System.IO; */
string fileName = "asd.txt";//客户端保存的文件名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路径
FileInfo fileInfo = new FileInfo(filePath); Response.Clear(); Response.ClearContent(); Response.ClearHeaders(); Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName); Response.AddHeader("Content-Length", fileInfo.Length.ToString()); Response.AddHeader("Content-Transfer-Encoding", "binary"); Response.ContentType = "application/octet-stream"; Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312"); Response.WriteFile(fileInfo.FullName); Response.Flush(); Response.End(); }
4.TransmitFile实现下载 protected void Button1_Click1(object sender, EventArgs e) { /* 微软为Response对象提供了一个新的方法TransmitFile来解决使用Response.BinaryWrite 下载超过400mb的文件时导致Aspnet_wp.exe进程回收而无法成功下载的问题。 代码如下： */ string strFileName = "三部闲置设备管理系统操作手册IEMS.ppt"; Response.ContentType = "application/x-zip-compressed"; //Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312"); string filename = BLL.Config.PART_EM_UPLOAD_DOC + strFileName;
//BLL.Config.PART_EM_UPLOAD_DOC 为路径 ("D:/EMUploadDoc/" ) Response.AddHeader("Content-Disposition", "attachment;filename=" +Server.UrlPathEncode(strFileName));
//Server.UrlPathEncode()解决文件名的乱码问题. Response.TransmitFile(filename); }
上传文件实例：
if (Fileupload.PostedFile.ContentLength > 0) //判断用户是否上传了文件 { string strfilename = Fileupload.PostedFile.FileName; //获取上传的路径及文件名 int i = strfilename.IndexOf(".");
// if (!System.IO.Directory.Exists(path)) Directory.CreateDirectory(path); 判断是否有上传的目录没有则创建此目录 string strnewname = strfilename.Substring(i); //获取上传文件的扩展名 DateTime dtTime = new DateTime(); string struploadname = Fileupload.FileName; //获取上传文件的文件名 //string struploadname = DateTime.Now.ToString("yyyyMMddhhmmss") // + Fileupload.PostedFile.ContentLength.ToString() + strnewname; //对文件进行重命名。名字为：年+月+日+文件大小 String path = Server.MapPath("~/FileUpload/ReceptionDataBase/"); //获取服务器文件夹 string fileurl = path + "\" + struploadname; Fileupload.PostedFile.SaveAs(fileurl); //将文件上传至服务器 resources.UploadFile = struploadname; //附件文件名
}
下载文件实例：
首先引用using System.IO;
if (!string.IsNullOrEmpty(this.FileName)) //判断是否有附件，从资料库读取附件名称FileName表示附件名称 { string filename = this.FileName; string filepath = "~/FileUpload/ReceptionDataBase/" + filename; string path = Server.MapPath(filepath); //获取文件路径
FileStream fs = new FileStream(path, FileMode.Open); byte[] bytes = new byte[(int)fs.Length]; fs.Read(bytes, 0, bytes.Length); fs.Close(); Response.ContentType = "application/octet-stream"; //通知浏览器下载文件不是打开文件 Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(filename, System.Text.Encoding.UTF8)); Response.TransmitFile(path); Response.BinaryWrite(bytes); Response.Flush(); Response.End();
//测试时不能用下载软件（迅雷等）下载符件 } else { this.ClientScriptAlert("此项目没有附件！"); } this.FileName = "";