ASP.NET教程：asp.net向客户端输出大文件代码

代码

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();

}

}