asp.net 瀏覽器下載檔案的四種方式
阿新 • • 發佈:2021-12-15
轉自 https://www.cnblogs.com/lgx5/p/10235567.html
// 方法一:TransmitFile實現下載 protected void Button1_Click(object sender, EventArgs e) { Response.ContentType = "application/x-zip-compressed"; Response.AddHeader("Content-Disposition", "attachment;filename=z.zip"); string filename = Server.MapPath("DownLoad/z.zip"); Response.TransmitFile(filename); }
ContentType 屬性指定響應的 HTTP 內容型別。如果未指定 ContentType,預設為 text/HTML。
語法 Response.ContentType [= ContentType ] 引數 ContentType 描述內容型別的字串。該字串通常被格式化為型別/子型別,其中型別是常規內容範疇而子類為特定內容型別。
// 方法二:WriteFile實現下載 protected void Button2_Click(object sender, EventArgs e) { string fileName = "asd.txt";//客戶端儲存的檔名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路徑 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(); }
response.write的意思是返回一個訊息給其它頁面也可以,當前頁面也行的。
// 方法三:WriteFile分塊下載 protected void Button3_Click(object sender, EventArgs e) { string fileName = "aaa.txt";//客戶端儲存的檔名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路徑 System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath); if (fileInfo.Exists == true) { const long ChunkSize = 102400;//100K 每次讀取檔案,只讀取100K,這樣可以緩解伺服器的壓力 byte[] buffer = new byte[ChunkSize]; Response.Clear(); System.IO.FileStream iStream = System.IO.File.OpenRead(filePath); long dataLengthToRead = iStream.Length;//獲取下載的檔案總大小 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));//讀取的大小 Response.OutputStream.Write(buffer, 0, lengthRead); Response.Flush(); dataLengthToRead = dataLengthToRead - lengthRead; } Response.Close(); } }
// 方法四:流方式下載 protected void Button4_Click(object sender, EventArgs e) { string fileName = "aaa.txt";//客戶端儲存的檔名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路徑 //以字元流的形式下載檔案 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"; //通知瀏覽器下載檔案而不是開啟 Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)); Response.BinaryWrite(bytes); Response.Flush(); Response.End(); }