
Code
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System.IO.Stream iStream = null;
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// Buffer to read 10K bytes in chunk:
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byte[] buffer = new Byte[10240];
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// Length of the file:
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int length;
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// Total bytes to read:
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long dataToRead;
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// Identify the file to download including its path.
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string filepath = @"E:\software\SQL Server 2000 Personal Edition.ISO";
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// Identify the file name.
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string filename = System.IO.Path.GetFileName(filepath);
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try
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{
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// Open the file.
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iStream = new System.IO.FileStream(filepath, System.IO.FileMode.Open,
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System.IO.FileAccess.Read,System.IO.FileShare.Read);
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Response.Clear();
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// Total bytes to read:
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dataToRead = iStream.Length;
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long p = 0;
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if(Request.Headers["Range"]!=null)
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{
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Response.StatusCode = 206;
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p = long.Parse( Request.Headers["Range"].Replace("bytes=","").Replace("-",""));
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}
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if(p != 0)
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{
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Response.AddHeader("Content-Range","bytes " + p.ToString() + "-" + ((long)(dataToRead - 1)).ToString() + "/" + dataToRead.ToString());
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}
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Response.AddHeader("Content-Length",((long)(dataToRead-p)).ToString());
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Response.ContentType = "application/octet-stream";
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Response.AddHeader("Content-Disposition", "attachment; filename=" + System.Web.HttpUtility.UrlEncode(Request.ContentEncoding.GetBytes(filename)));
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iStream.Position = p;
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dataToRead = dataToRead - p;
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// Read the bytes.
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while (dataToRead > 0)
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{
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// Verify that the client is connected.
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if (Response.IsClientConnected)
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{
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// Read the data in buffer.
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length = iStream.Read(buffer, 0, 10240);
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// Write the data to the current output stream.
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Response.OutputStream.Write(buffer, 0, length);
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// Flush the data to the HTML output.
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Response.Flush();
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buffer= new Byte[10240];
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dataToRead = dataToRead - length;
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}
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else
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{
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//prevent infinite loop if user disconnects
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dataToRead = -1;
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}
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}
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}
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catch (Exception ex)
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{
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// Trap the error, if any.
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Response.Write("Error : " + ex.Message);
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}
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finally
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{
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if (iStream != null)
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{
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//Close the file.
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iStream.Close();
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}
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Response.End();
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}
转载于:https://www.cnblogs.com/zhangchenliang/archive/2007/12/03/981239.html