C#实现大文件分块发送到客户端

System.IO.Stream iStream = null;
// Buffer to read 10K bytes in chunk:
byte[] buffer = new Byte[10000];
// Length of the file:
int length;
// Total bytes to read:
long dataToRead;
// Identify the file to download including its path.
string filepath = "DownloadFileName";
// Identify the file name.
string filename = System.IO.Path.GetFileName(filepath);
try
{
// Open the file.
iStream = new System.IO.FileStream(filepath, System.IO.FileMode.Open,
System.IO.FileAccess.Read,System.IO.FileShare.Read);
// Total bytes to read:
dataToRead = iStream.Length;
Response.ContentType = "application/octet-stream";
Response.AddHeader("Content-Disposition", "attachment; filename=" + filename);
// Read the bytes.
while (dataToRead > 0)
{
// Verify that the client is connected.
if (Response.IsClientConnected)
{
// Read the data in buffer.
length = iStream.Read(buffer, 0, 10000);
// Write the data to the current output stream.
Response.OutputStream.Write(buffer, 0, length);
// Flush the data to the HTML output.
Response.Flush();
buffer= new Byte[10000];
dataToRead = dataToRead - length;
}
else
{
//prevent infinite loop if user disconnects
dataToRead = -1;
}
}
}
catch (Exception ex)
{
// Trap the error, if any.
Response.Write("Error : " + ex.Message);
}
finally
{
if (iStream != null)
{
//Close the file.
iStream.Close();
}
}