BufferedStream BufferedStream BufferedStream BufferedStream Class

定义

将缓冲层添加到另一个流上的读取和写入操作。Adds a buffering layer to read and write operations on another stream. 此类不能被继承。This class cannot be inherited.

public ref class BufferedStream sealed : System::IO::Stream
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class BufferedStream : System.IO.Stream
type BufferedStream = class
    inherit Stream
Public NotInheritable Class BufferedStream
Inherits Stream
继承
属性

示例

下面的代码示例演示如何使用BufferedStream类通过NetworkStream类,以提高某些 I/O 操作的性能。The following code examples show how to use the BufferedStream class over the NetworkStream class to increase the performance of certain I/O operations. 在开始客户端之前在远程计算机上启动服务器。Start the server on a remote computer before starting the client. 启动客户端时,请指定远程计算机名称作为命令行参数。Specify the remote computer name as a command-line argument when starting the client. 改变dataArraySizestreamBufferSize常量以查看对性能的影响。Vary the dataArraySize and streamBufferSize constants to view their effect on performance.

第一个示例显示了在客户端运行的代码和第二个示例显示了在服务器运行的代码。The first example shows the code that runs on the client, and the second example shows the code that runs on the server.

示例 1:在客户端运行的代码Example 1: Code that runs on the client

#using <system.dll>

using namespace System;
using namespace System::IO;
using namespace System::Globalization;
using namespace System::Net;
using namespace System::Net::Sockets;
static const int streamBufferSize = 1000;
public ref class Client
{
private:
   literal int dataArraySize = 100;
   literal int numberOfLoops = 10000;
   Client(){}


public:
   static void ReceiveData( Stream^ netStream, Stream^ bufStream )
   {
      DateTime startTime;
      Double networkTime;
      Double bufferedTime = 0;
      int bytesReceived = 0;
      array<Byte>^receivedData = gcnew array<Byte>(dataArraySize);
      
      // Receive data using the NetworkStream.
      Console::WriteLine( "Receiving data using NetworkStream." );
      startTime = DateTime::Now;
      while ( bytesReceived < numberOfLoops * receivedData->Length )
      {
         bytesReceived += netStream->Read( receivedData, 0, receivedData->Length );
      }

      networkTime = (DateTime::Now - startTime).TotalSeconds;
      Console::WriteLine( "{0} bytes received in {1} seconds.\n", bytesReceived.ToString(), networkTime.ToString(  "F1" ) );
      
      // Receive data using the BufferedStream.
      Console::WriteLine(  "Receiving data using BufferedStream." );
      bytesReceived = 0;
      startTime = DateTime::Now;
      while ( bytesReceived < numberOfLoops * receivedData->Length )
      {
         bytesReceived += bufStream->Read( receivedData, 0, receivedData->Length );
      }

      bufferedTime = (DateTime::Now - startTime).TotalSeconds;
      Console::WriteLine( "{0} bytes received in {1} seconds.\n", bytesReceived.ToString(), bufferedTime.ToString(  "F1" ) );
      
      // Print the ratio of read times.
      Console::WriteLine( "Receiving data using the buffered "
      "network stream was {0} {1} than using the network "
      "stream alone.", (networkTime / bufferedTime).ToString(  "P0" ), bufferedTime < networkTime ? (String^)"faster" : "slower" );
   }

   static void SendData( Stream^ netStream, Stream^ bufStream )
   {
      DateTime startTime;
      Double networkTime;
      Double bufferedTime;
      
      // Create random data to send to the server.
      array<Byte>^dataToSend = gcnew array<Byte>(dataArraySize);
      (gcnew Random)->NextBytes( dataToSend );
      
      // Send the data using the NetworkStream.
      Console::WriteLine( "Sending data using NetworkStream." );
      startTime = DateTime::Now;
      for ( int i = 0; i < numberOfLoops; i++ )
      {
         netStream->Write( dataToSend, 0, dataToSend->Length );

      }
      networkTime = (DateTime::Now - startTime).TotalSeconds;
      Console::WriteLine( "{0} bytes sent in {1} seconds.\n", (numberOfLoops * dataToSend->Length).ToString(), networkTime.ToString(  "F1" ) );
      
      // Send the data using the BufferedStream.
      Console::WriteLine( "Sending data using BufferedStream." );
      startTime = DateTime::Now;
      for ( int i = 0; i < numberOfLoops; i++ )
      {
         bufStream->Write( dataToSend, 0, dataToSend->Length );

      }
      bufStream->Flush();
      bufferedTime = (DateTime::Now - startTime).TotalSeconds;
      Console::WriteLine( "{0} bytes sent in {1} seconds.\n", (numberOfLoops * dataToSend->Length).ToString(), bufferedTime.ToString(  "F1" ) );
      
      // Print the ratio of write times.
      Console::WriteLine( "Sending data using the buffered "
      "network stream was {0} {1} than using the network "
      "stream alone.\n", (networkTime / bufferedTime).ToString(  "P0" ), bufferedTime < networkTime ? (String^)"faster" : "slower" );
   }

};

int main( int argc, char *argv[] )
{
   
   // Check that an argument was specified when the 
   // program was invoked.
   if ( argc == 1 )
   {
      Console::WriteLine( "Error: The name of the host computer"
      " must be specified when the program is invoked." );
      return  -1;
   }

   String^ remoteName = gcnew String( argv[ 1 ] );
   
   // Create the underlying socket and connect to the server.
   Socket^ clientSocket = gcnew Socket( AddressFamily::InterNetwork,SocketType::Stream,ProtocolType::Tcp );
   clientSocket->Connect( gcnew IPEndPoint( Dns::Resolve( remoteName )->AddressList[ 0 ],1800 ) );
   Console::WriteLine(  "Client is connected.\n" );
   
   // Create a NetworkStream that owns clientSocket and 
   // then create a BufferedStream on top of the NetworkStream.
   NetworkStream^ netStream = gcnew NetworkStream( clientSocket,true );
   BufferedStream^ bufStream = gcnew BufferedStream( netStream,streamBufferSize );
   
   try
   {
      
      // Check whether the underlying stream supports seeking.
      Console::WriteLine( "NetworkStream {0} seeking.\n", bufStream->CanSeek ? (String^)"supports" : "does not support" );
      
      // Send and receive data.
      if ( bufStream->CanWrite )
      {
         Client::SendData( netStream, bufStream );
      }
      
      if ( bufStream->CanRead )
      {
         Client::ReceiveData( netStream, bufStream );
      }
      
   }
   finally
   {
      
      // When bufStream is closed, netStream is in turn closed,
      // which in turn shuts down the connection and closes
      // clientSocket.
      Console::WriteLine( "\nShutting down connection." );
      bufStream->Close();
      
   }

}

using System;
using System.IO;
using System.Globalization;
using System.Net;
using System.Net.Sockets;

public class Client
{
    const int dataArraySize    =   100;
    const int streamBufferSize =  1000;
    const int numberOfLoops    = 10000;

    static void Main(string[] args)
    {
        // Check that an argument was specified when the
        // program was invoked.
        if(args.Length == 0)
        {
            Console.WriteLine("Error: The name of the host computer" +
                " must be specified when the program is invoked.");
            return;
        }

        string remoteName = args[0];

        // Create the underlying socket and connect to the server.
        Socket clientSocket = new Socket(AddressFamily.InterNetwork,
            SocketType.Stream, ProtocolType.Tcp);

        clientSocket.Connect(new IPEndPoint(
            Dns.Resolve(remoteName).AddressList[0], 1800));

        Console.WriteLine("Client is connected.\n");

        // Create a NetworkStream that owns clientSocket and
        // then create a BufferedStream on top of the NetworkStream.
        // Both streams are disposed when execution exits the
        // using statement.
        using(Stream
            netStream = new NetworkStream(clientSocket, true),
            bufStream =
                  new BufferedStream(netStream, streamBufferSize))
        {
            // Check whether the underlying stream supports seeking.
            Console.WriteLine("NetworkStream {0} seeking.\n",
                bufStream.CanSeek ? "supports" : "does not support");

            // Send and receive data.
            if(bufStream.CanWrite)
            {
                SendData(netStream, bufStream);
            }
            if(bufStream.CanRead)
            {
                ReceiveData(netStream, bufStream);
            }

            // When bufStream is closed, netStream is in turn
            // closed, which in turn shuts down the connection
            // and closes clientSocket.
            Console.WriteLine("\nShutting down the connection.");
            bufStream.Close();
        }
    }

    static void SendData(Stream netStream, Stream bufStream)
    {
        DateTime startTime;
        double networkTime, bufferedTime;

        // Create random data to send to the server.
        byte[] dataToSend = new byte[dataArraySize];
        new Random().NextBytes(dataToSend);

        // Send the data using the NetworkStream.
        Console.WriteLine("Sending data using NetworkStream.");
        startTime = DateTime.Now;
        for(int i = 0; i < numberOfLoops; i++)
        {
            netStream.Write(dataToSend, 0, dataToSend.Length);
        }
        networkTime = (DateTime.Now - startTime).TotalSeconds;
        Console.WriteLine("{0} bytes sent in {1} seconds.\n",
            numberOfLoops * dataToSend.Length,
            networkTime.ToString("F1"));

        // Send the data using the BufferedStream.
        Console.WriteLine("Sending data using BufferedStream.");
        startTime = DateTime.Now;
        for(int i = 0; i < numberOfLoops; i++)
        {
            bufStream.Write(dataToSend, 0, dataToSend.Length);
        }
        bufStream.Flush();
        bufferedTime = (DateTime.Now - startTime).TotalSeconds;
        Console.WriteLine("{0} bytes sent in {1} seconds.\n",
            numberOfLoops * dataToSend.Length,
            bufferedTime.ToString("F1"));

        // Print the ratio of write times.
        Console.WriteLine("Sending data using the buffered " +
            "network stream was {0} {1} than using the network " +
            "stream alone.\n",
            (networkTime/bufferedTime).ToString("P0"),
            bufferedTime < networkTime ? "faster" : "slower");
    }

    static void ReceiveData(Stream netStream, Stream bufStream)
    {
        DateTime startTime;
        double networkTime, bufferedTime = 0;
        int bytesReceived = 0;
        byte[] receivedData = new byte[dataArraySize];

        // Receive data using the NetworkStream.
        Console.WriteLine("Receiving data using NetworkStream.");
        startTime = DateTime.Now;
        while(bytesReceived < numberOfLoops * receivedData.Length)
        {
            bytesReceived += netStream.Read(
                receivedData, 0, receivedData.Length);
        }
        networkTime = (DateTime.Now - startTime).TotalSeconds;
        Console.WriteLine("{0} bytes received in {1} seconds.\n",
            bytesReceived.ToString(),
            networkTime.ToString("F1"));

        // Receive data using the BufferedStream.
        Console.WriteLine("Receiving data using BufferedStream.");
        bytesReceived = 0;
        startTime = DateTime.Now;

        int numBytesToRead = receivedData.Length;

        while (numBytesToRead > 0)
        {
            // Read may return anything from 0 to numBytesToRead.
            int n = bufStream.Read(receivedData,0, receivedData.Length);
            // The end of the file is reached.
            if (n == 0)
                break;
            bytesReceived += n;
            numBytesToRead -= n;
        }

        bufferedTime = (DateTime.Now - startTime).TotalSeconds;
        Console.WriteLine("{0} bytes received in {1} seconds.\n",
            bytesReceived.ToString(),
            bufferedTime.ToString("F1"));

        // Print the ratio of read times.
        Console.WriteLine("Receiving data using the buffered network" +
            " stream was {0} {1} than using the network stream alone.",
            (networkTime/bufferedTime).ToString("P0"),
            bufferedTime < networkTime ? "faster" : "slower");
    }
}
' Compile using /r:System.dll.
Imports Microsoft.VisualBasic
Imports System
Imports System.IO
Imports System.Globalization
Imports System.Net
Imports System.Net.Sockets

Public Class Client 

    Const dataArraySize As Integer    =   100
    Const streamBufferSize As Integer =  1000
    Const numberOfLoops As Integer    = 10000

    Shared Sub Main(args As String()) 
    
        ' Check that an argument was specified when the 
        ' program was invoked.
        If args.Length = 0 Then
            Console.WriteLine("Error: The name of the host " & _
                "computer must be specified when the program " & _ 
                "is invoked.")
            Return
        End If

        Dim remoteName As String = args(0)

        ' Create the underlying socket and connect to the server.
        Dim clientSocket As New Socket(AddressFamily.InterNetwork, _
            SocketType.Stream, ProtocolType.Tcp)

        clientSocket.Connect(New IPEndPoint( _
            Dns.Resolve(remoteName).AddressList(0), 1800))

        Console.WriteLine("Client is connected." & vbCrLf)

        ' Create a NetworkStream that owns clientSocket and then 
        ' create a BufferedStream on top of the NetworkStream.
        Dim netStream As New NetworkStream(clientSocket, True)
        Dim bufStream As New _
            BufferedStream(netStream, streamBufferSize)
        
        Try
            ' Check whether the underlying stream supports seeking.
            If bufStream.CanSeek Then
                Console.WriteLine("NetworkStream supports" & _
                    "seeking." & vbCrLf)
            Else
                Console.WriteLine("NetworkStream does not " & _
                    "support seeking." & vbCrLf)
            End If

            ' Send and receive data.
            If bufStream.CanWrite Then
                SendData(netStream, bufStream)
            End If            
            If bufStream.CanRead Then
                ReceiveData(netStream, bufStream)
            End If
        Finally

            ' When bufStream is closed, netStream is in turn 
            ' closed, which in turn shuts down the connection 
            ' and closes clientSocket.
            Console.WriteLine(vbCrLf & "Shutting down the connection.")
            bufStream.Close()
        End Try
    End Sub

    Shared Sub SendData(netStream As Stream, bufStream As Stream)
    
        Dim startTime As DateTime 
        Dim networkTime As Double, bufferedTime As Double 

        ' Create random data to send to the server.
        Dim dataToSend(dataArraySize - 1) As Byte
        Dim randomGenerator As New Random()
        randomGenerator.NextBytes(dataToSend)

        ' Send the data using the NetworkStream.
        Console.WriteLine("Sending data using NetworkStream.")
        startTime = DateTime.Now
        For i As Integer = 1 To numberOfLoops
            netStream.Write(dataToSend, 0, dataToSend.Length)
        Next i
        networkTime = DateTime.Now.Subtract(startTime).TotalSeconds
        Console.WriteLine("{0} bytes sent in {1} seconds." & vbCrLf, _
            numberOfLoops * dataToSend.Length, _
            networkTime.ToString("F1"))

        ' Send the data using the BufferedStream.
        Console.WriteLine("Sending data using BufferedStream.")
        startTime = DateTime.Now
        For i As Integer = 1 To numberOfLoops
            bufStream.Write(dataToSend, 0, dataToSend.Length)
        Next i
        
        bufStream.Flush()
        bufferedTime = DateTime.Now.Subtract(startTime).TotalSeconds
        Console.WriteLine("{0} bytes sent In {1} seconds." & vbCrLf, _
            numberOfLoops * dataToSend.Length, _
            bufferedTime.ToString("F1"))

        ' Print the ratio of write times.
        Console.Write("Sending data using the buffered " & _
            "network stream was {0}", _
            (networkTime/bufferedTime).ToString("P0"))
        If bufferedTime < networkTime Then
            Console.Write(" faster")
        Else
            Console.Write(" slower")
        End If
        Console.WriteLine(" than using the network stream alone.")
    End Sub

    Shared Sub ReceiveData(netStream As Stream, bufStream As Stream)
    
        Dim startTime As DateTime 
        Dim networkTime As Double, bufferedTime As Double = 0

        Dim bytesReceived As Integer = 0
        Dim receivedData(dataArraySize - 1) As Byte

        ' Receive data using the NetworkStream.
        Console.WriteLine("Receiving data using NetworkStream.")
        startTime = DateTime.Now
        While bytesReceived < numberOfLoops * receivedData.Length
            bytesReceived += netStream.Read( _
                receivedData, 0, receivedData.Length)
        End While
        networkTime = DateTime.Now.Subtract(startTime).TotalSeconds
        Console.WriteLine("{0} bytes received in {1} " & _
            "seconds." & vbCrLf, _
            bytesReceived.ToString(), _
            networkTime.ToString("F1"))

        ' Receive data using the BufferedStream.
        Console.WriteLine("Receiving data using BufferedStream.")
        bytesReceived = 0
        startTime = DateTime.Now

        Dim numBytesToRead As Integer = receivedData.Length
        Dim n As Integer
        Do While numBytesToRead > 0

            'Read my return anything from 0 to numBytesToRead
            n = bufStream.Read(receivedData, 0, receivedData.Length)
            'The end of the file is reached.
            If n = 0 Then
                Exit Do
            End If

            bytesReceived += n
            numBytesToRead -= n
        Loop

        bufferedTime = DateTime.Now.Subtract(startTime).TotalSeconds
        Console.WriteLine("{0} bytes received in {1} " & _
            "seconds." & vbCrLf, _
            bytesReceived.ToString(), _
            bufferedTime.ToString("F1"))

        ' Print the ratio of read times.
        Console.Write("Receiving data using the buffered " & _
            "network stream was {0}", _
            (networkTime/bufferedTime).ToString("P0"))
        If bufferedTime < networkTime Then
            Console.Write(" faster")
        Else
            Console.Write(" slower")
        End If
        Console.WriteLine(" than using the network stream alone.")
    End Sub
End Class

示例 2:在服务器运行的代码Example 2: Code that runs on the server

#using <system.dll>

using namespace System;
using namespace System::Net;
using namespace System::Net::Sockets;
int main()
{
   
   // This is a Windows Sockets 2 error code.
   const int WSAETIMEDOUT = 10060;
   Socket^ serverSocket;
   int bytesReceived;
   int totalReceived = 0;
   array<Byte>^receivedData = gcnew array<Byte>(2000000);
   
   // Create random data to send to the client.
   array<Byte>^dataToSend = gcnew array<Byte>(2000000);
   (gcnew Random)->NextBytes( dataToSend );
   IPAddress^ ipAddress = Dns::Resolve( Dns::GetHostName() )->AddressList[ 0 ];
   IPEndPoint^ ipEndpoint = gcnew IPEndPoint( ipAddress,1800 );
   
   // Create a socket and listen for incoming connections.
   Socket^ listenSocket = gcnew Socket( AddressFamily::InterNetwork,SocketType::Stream,ProtocolType::Tcp );
   try
   {
      listenSocket->Bind( ipEndpoint );
      listenSocket->Listen( 1 );
      
      // Accept a connection and create a socket to handle it.
      serverSocket = listenSocket->Accept();
      Console::WriteLine( "Server is connected.\n" );
   }
   finally
   {
      listenSocket->Close();
   }

   try
   {
      
      // Send data to the client.
      Console::Write( "Sending data ... " );
      int bytesSent = serverSocket->Send( dataToSend, 0, dataToSend->Length, SocketFlags::None );
      Console::WriteLine( "{0} bytes sent.\n", bytesSent.ToString() );
      
      // Set the timeout for receiving data to 2 seconds.
      serverSocket->SetSocketOption( SocketOptionLevel::Socket, SocketOptionName::ReceiveTimeout, 2000 );
      
      // Receive data from the client.
      Console::Write( "Receiving data ... " );
      try
      {
         do
         {
            bytesReceived = serverSocket->Receive( receivedData, 0, receivedData->Length, SocketFlags::None );
            totalReceived += bytesReceived;
         }
         while ( bytesReceived != 0 );
      }
      catch ( SocketException^ e ) 
      {
         if ( e->ErrorCode == WSAETIMEDOUT )
         {
            
            // Data was not received within the given time.
            // Assume that the transmission has ended.
         }
         else
         {
            Console::WriteLine( "{0}: {1}\n", e->GetType()->Name, e->Message );
         }
      }
      finally
      {
         Console::WriteLine( "{0} bytes received.\n", totalReceived.ToString() );
      }

   }
   finally
   {
      serverSocket->Shutdown( SocketShutdown::Both );
      Console::WriteLine( "Connection shut down." );
      serverSocket->Close();
   }

}

using System;
using System.Net;
using System.Net.Sockets;

public class Server 
{
    static void Main() 
    {
        // This is a Windows Sockets 2 error code.
        const int WSAETIMEDOUT = 10060;

        Socket serverSocket;
        int bytesReceived, totalReceived = 0;
        byte[] receivedData = new byte[2000000];

        // Create random data to send to the client.
        byte[] dataToSend = new byte[2000000];
        new Random().NextBytes(dataToSend);

        IPAddress ipAddress =
            Dns.Resolve(Dns.GetHostName()).AddressList[0];

        IPEndPoint ipEndpoint = new IPEndPoint(ipAddress, 1800);

        // Create a socket and listen for incoming connections.
        using(Socket listenSocket = new Socket(
            AddressFamily.InterNetwork, SocketType.Stream, 
            ProtocolType.Tcp))
        {
            listenSocket.Bind(ipEndpoint);
            listenSocket.Listen(1);

            // Accept a connection and create a socket to handle it.
            serverSocket = listenSocket.Accept();
            Console.WriteLine("Server is connected.\n");
        }

        try
        {
            // Send data to the client.
            Console.Write("Sending data ... ");
            int bytesSent = serverSocket.Send(
                dataToSend, 0, dataToSend.Length, SocketFlags.None);
            Console.WriteLine("{0} bytes sent.\n", 
                bytesSent.ToString());

            // Set the timeout for receiving data to 2 seconds.
            serverSocket.SetSocketOption(SocketOptionLevel.Socket,
                SocketOptionName.ReceiveTimeout, 2000);

            // Receive data from the client.
            Console.Write("Receiving data ... ");
            try
            {
                do
                {
                    bytesReceived = serverSocket.Receive(receivedData,
                        0, receivedData.Length, SocketFlags.None);
                    totalReceived += bytesReceived;
                }
                while(bytesReceived != 0);
            }
            catch(SocketException e)
            {
                if(e.ErrorCode == WSAETIMEDOUT)
                {
                    // Data was not received within the given time.
                    // Assume that the transmission has ended.
                }
                else
                {
                    Console.WriteLine("{0}: {1}\n", 
                        e.GetType().Name, e.Message);
                }
            }
            finally
            {
                Console.WriteLine("{0} bytes received.\n",
                    totalReceived.ToString());
            }
        }
        finally
        {
            serverSocket.Shutdown(SocketShutdown.Both);
            Console.WriteLine("Connection shut down.");
            serverSocket.Close();
        }
    }
}
' Compile using /r:System.dll.
Imports Microsoft.VisualBasic
Imports System
Imports System.Net
Imports System.Net.Sockets

Public Class Server 

    Shared Sub Main() 
    
        ' This is a Windows Sockets 2 error code.
        Const WSAETIMEDOUT As Integer = 10060

        Dim serverSocket As Socket 
        Dim bytesReceived As Integer
        Dim totalReceived As Integer = 0
        Dim receivedData(2000000-1) As Byte

        ' Create random data to send to the client.
        Dim dataToSend(2000000-1) As Byte
        Dim randomGenerator As New Random()
        randomGenerator.NextBytes(dataToSend)

        Dim ipAddress As IPAddress = _
            Dns.Resolve(Dns.GetHostName()).AddressList(0)

        Dim ipEndpoint As New IPEndPoint(ipAddress, 1800)

        ' Create a socket and listen for incoming connections.
        Dim listenSocket As New Socket(AddressFamily.InterNetwork, _
            SocketType.Stream, ProtocolType.Tcp)
        
        Try
            listenSocket.Bind(ipEndpoint)
            listenSocket.Listen(1)

            ' Accept a connection and create a socket to handle it.
            serverSocket = listenSocket.Accept()
            Console.WriteLine("Server is connected." & vbCrLf)
        Finally
            listenSocket.Close()
        End Try

        Try
            ' Send data to the client.
            Console.Write("Sending data ... ")
            Dim bytesSent As Integer = serverSocket.Send( _
                dataToSend, 0, dataToSend.Length, SocketFlags.None)
            Console.WriteLine("{0} bytes sent." & vbCrLf, _
                bytesSent.ToString())

            ' Set the timeout for receiving data to 2 seconds.
            serverSocket.SetSocketOption(SocketOptionLevel.Socket, _
                SocketOptionName.ReceiveTimeout, 2000)

            ' Receive data from the client.
            Console.Write("Receiving data ... ")
            Try
                Do
                    bytesReceived = serverSocket.Receive( _
                        receivedData, 0, receivedData.Length, _
                        SocketFlags.None)
                    totalReceived += bytesReceived
                Loop While bytesReceived <> 0
            Catch e As SocketException
                If(e.ErrorCode = WSAETIMEDOUT)
                
                    ' Data was not received within the given time.
                    ' Assume that the transmission has ended.
                Else
                    Console.WriteLine("{0}: {1}" & vbCrLf, _
                        e.GetType().Name, e.Message)
                End If
            Finally
                Console.WriteLine("{0} bytes received." & vbCrLf, _
                    totalReceived.ToString())
            End Try
        Finally
            serverSocket.Shutdown(SocketShutdown.Both)
            Console.WriteLine("Connection shut down.")
            serverSocket.Close()
        End Try
    
    End Sub
End Class

注解

一个缓冲区就是内存用于缓存数据,从而减少了对操作系统的调用中的字节块。A buffer is a block of bytes in memory used to cache data, thereby reducing the number of calls to the operating system. 缓冲区提高读取和写入性能。Buffers improve read and write performance. 缓冲区可以同时使用的是读取或写入,但永远不会同时。A buffer can be used for either reading or writing, but never both simultaneously. ReadWrite方法的BufferedStream自动维护缓冲区。The Read and Write methods of BufferedStream automatically maintain the buffer.

重要

此类型实现IDisposable接口。This type implements the IDisposable interface. 在使用完类型后,您应直接或间接释放类型。When you have finished using the type, you should dispose of it either directly or indirectly. 若要直接释放类型,调用其Dispose中的方法try / catch块。To dispose of the type directly, call its Dispose method in a try/catch block. 若要间接释放类型,请使用 using(在 C# 中)或 Using(在 Visual Basic 中)等语言构造。To dispose of it indirectly, use a language construct such as using (in C#) or Using (in Visual Basic). 有关详细信息,请参阅中的"使用对象实现 IDisposable"一节IDisposable接口主题。For more information, see the "Using an Object that Implements IDisposable" section in the IDisposable interface topic.

BufferedStream 可以是围绕某些类型的流组成。BufferedStream can be composed around certain types of streams. 它提供用于读取和字节写入到基础数据源或存储库的实现。It provides implementations for reading and writing bytes to an underlying data source or repository. 使用BinaryReaderBinaryWriter用于读取和写入其他数据类型。Use BinaryReader and BinaryWriter for reading and writing other data types. BufferedStream 设计是为了防止从减的前提下输入和输出时不需要缓冲区的缓冲区。BufferedStream is designed to prevent the buffer from slowing down input and output when the buffer is not needed. 如果始终读取和写入的大小大于内部缓冲区的大小,然后BufferedStream可能甚至无法分配内部缓冲区。If you always read and write for sizes greater than the internal buffer size, then BufferedStream might not even allocate the internal buffer. BufferedStream 此外缓冲读取和写入的共享缓冲区中。BufferedStream also buffers reads and writes in a shared buffer. 假定您将几乎总是会执行一系列的读取或写入,但很少会交替使用这两个孩子。It is assumed that you will almost always be doing a series of reads or writes, but rarely alternate between the two of them.

构造函数

BufferedStream(Stream) BufferedStream(Stream) BufferedStream(Stream) BufferedStream(Stream)

使用默认的缓冲区大小 4096 字节初始化 BufferedStream 类的新实例。Initializes a new instance of the BufferedStream class with a default buffer size of 4096 bytes.

BufferedStream(Stream, Int32) BufferedStream(Stream, Int32) BufferedStream(Stream, Int32) BufferedStream(Stream, Int32)

使用指定的缓冲区大小初始化 BufferedStream 类的新实例。Initializes a new instance of the BufferedStream class with the specified buffer size.

属性

BufferSize BufferSize BufferSize BufferSize
CanRead CanRead CanRead CanRead

获取一个值,该值指示当前流是否支持读取。Gets a value indicating whether the current stream supports reading.

CanSeek CanSeek CanSeek CanSeek

获取一个值,该值指示当前流是否支持查找。Gets a value indicating whether the current stream supports seeking.

CanTimeout CanTimeout CanTimeout CanTimeout

获取一个值,该值确定当前流是否可以超时。Gets a value that determines whether the current stream can time out.

(Inherited from Stream)
CanWrite CanWrite CanWrite CanWrite

获取一个值,该值指示当前流是否支持写入。Gets a value indicating whether the current stream supports writing.

Length Length Length Length

获取流长度,长度以字节为单位。Gets the stream length in bytes.

Position Position Position Position

获取当前流内的位置。Gets the position within the current stream.

ReadTimeout ReadTimeout ReadTimeout ReadTimeout

获取或设置一个值(以毫秒为单位),该值确定流在超时前尝试读取多长时间。Gets or sets a value, in milliseconds, that determines how long the stream will attempt to read before timing out.

(Inherited from Stream)
UnderlyingStream UnderlyingStream UnderlyingStream UnderlyingStream
WriteTimeout WriteTimeout WriteTimeout WriteTimeout

获取或设置一个值(以毫秒为单位),该值确定流在超时前尝试写入多长时间。Gets or sets a value, in milliseconds, that determines how long the stream will attempt to write before timing out.

(Inherited from Stream)

方法

BeginRead(Byte[], Int32, Int32, AsyncCallback, Object) BeginRead(Byte[], Int32, Int32, AsyncCallback, Object) BeginRead(Byte[], Int32, Int32, AsyncCallback, Object) BeginRead(Byte[], Int32, Int32, AsyncCallback, Object)

开始异步读操作。Begins an asynchronous read operation. (请考虑改用 ReadAsync(Byte[], Int32, Int32, CancellationToken)。)(Consider using ReadAsync(Byte[], Int32, Int32, CancellationToken) instead.)

BeginWrite(Byte[], Int32, Int32, AsyncCallback, Object) BeginWrite(Byte[], Int32, Int32, AsyncCallback, Object) BeginWrite(Byte[], Int32, Int32, AsyncCallback, Object) BeginWrite(Byte[], Int32, Int32, AsyncCallback, Object)

开始异步写操作。Begins an asynchronous write operation. (请考虑改用 WriteAsync(Byte[], Int32, Int32, CancellationToken)。)(Consider using WriteAsync(Byte[], Int32, Int32, CancellationToken) instead.)

Close() Close() Close() Close()

关闭流并释放与当前缓冲流关联的所有资源(尤其是系统资源,如套接字和文件句柄)。Closes the stream and releases any resources (especially system resources such as sockets and file handles) associated with the current buffered stream.

CopyTo(Stream) CopyTo(Stream) CopyTo(Stream) CopyTo(Stream)

从当前流中读取字节并将其写入到另一流中。Reads the bytes from the current stream and writes them to another stream.

(Inherited from Stream)
CopyTo(Stream, Int32) CopyTo(Stream, Int32) CopyTo(Stream, Int32) CopyTo(Stream, Int32)
CopyToAsync(Stream) CopyToAsync(Stream) CopyToAsync(Stream) CopyToAsync(Stream)

从当前流中异步读取字节并将其写入到另一个流中。Asynchronously reads the bytes from the current stream and writes them to another stream.

(Inherited from Stream)
CopyToAsync(Stream, CancellationToken) CopyToAsync(Stream, CancellationToken) CopyToAsync(Stream, CancellationToken) CopyToAsync(Stream, CancellationToken)

通过指定的取消令牌,从当前流中异步读取字节并将其写入到另一个流中。Asynchronously reads the bytes from the current stream and writes them to another stream, using a specified cancellation token.

(Inherited from Stream)
CopyToAsync(Stream, Int32) CopyToAsync(Stream, Int32) CopyToAsync(Stream, Int32) CopyToAsync(Stream, Int32)

使用指定的缓冲区大小,从当前流中异步读取字节并将其写入到另一流中。Asynchronously reads the bytes from the current stream and writes them to another stream, using a specified buffer size.

(Inherited from Stream)
CopyToAsync(Stream, Int32, CancellationToken) CopyToAsync(Stream, Int32, CancellationToken) CopyToAsync(Stream, Int32, CancellationToken) CopyToAsync(Stream, Int32, CancellationToken)
CreateObjRef(Type) CreateObjRef(Type) CreateObjRef(Type) CreateObjRef(Type)

创建一个对象,该对象包含生成用于与远程对象进行通信的代理所需的全部相关信息。Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.

(Inherited from MarshalByRefObject)
CreateWaitHandle() CreateWaitHandle() CreateWaitHandle() CreateWaitHandle()

分配 WaitHandle 对象。Allocates a WaitHandle object.

(Inherited from Stream)
Dispose() Dispose() Dispose() Dispose()

释放由 Stream 使用的所有资源。Releases all resources used by the Stream.

(Inherited from Stream)
Dispose(Boolean) Dispose(Boolean) Dispose(Boolean) Dispose(Boolean)

释放由 Stream 占用的非托管资源,还可以另外再释放托管资源。Releases the unmanaged resources used by the Stream and optionally releases the managed resources.

(Inherited from Stream)
DisposeAsync() DisposeAsync() DisposeAsync() DisposeAsync()
EndRead(IAsyncResult) EndRead(IAsyncResult) EndRead(IAsyncResult) EndRead(IAsyncResult)

等待挂起的异步读操作完成。Waits for the pending asynchronous read operation to complete. (请考虑改用 ReadAsync(Byte[], Int32, Int32, CancellationToken)。)(Consider using ReadAsync(Byte[], Int32, Int32, CancellationToken) instead.)

EndWrite(IAsyncResult) EndWrite(IAsyncResult) EndWrite(IAsyncResult) EndWrite(IAsyncResult)

结束异步写入操作,在 I/O 操作完成之前一直阻止。Ends an asynchronous write operation and blocks until the I/O operation is complete. (请考虑改用 WriteAsync(Byte[], Int32, Int32, CancellationToken)。)(Consider using WriteAsync(Byte[], Int32, Int32, CancellationToken) instead.)

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

确定指定的对象是否等于当前对象。Determines whether the specified object is equal to the current object.

(Inherited from Object)
Flush() Flush() Flush() Flush()

清除此流的所有缓冲区并导致所有缓冲数据都写入基础设备中。Clears all buffers for this stream and causes any buffered data to be written to the underlying device.

FlushAsync() FlushAsync() FlushAsync() FlushAsync()

异步清除此流的所有缓冲区并导致所有缓冲数据都写入基础设备中。Asynchronously clears all buffers for this stream and causes any buffered data to be written to the underlying device.

(Inherited from Stream)
FlushAsync(CancellationToken) FlushAsync(CancellationToken) FlushAsync(CancellationToken) FlushAsync(CancellationToken)

异步清理这个流的所有缓冲区,并使所有缓冲数据写入基础设备,并且监控取消请求。Asynchronously clears all buffers for this stream, causes any buffered data to be written to the underlying device, and monitors cancellation requests.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

作为默认哈希函数。Serves as the default hash function.

(Inherited from Object)
GetLifetimeService() GetLifetimeService() GetLifetimeService() GetLifetimeService()

检索控制此实例的生存期策略的当前生存期服务对象。Retrieves the current lifetime service object that controls the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
GetType() GetType() GetType() GetType()

获取当前实例的 TypeGets the Type of the current instance.

(Inherited from Object)
InitializeLifetimeService() InitializeLifetimeService() InitializeLifetimeService() InitializeLifetimeService()

获取生存期服务对象来控制此实例的生存期策略。Obtains a lifetime service object to control the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

创建当前 Object 的浅表副本。Creates a shallow copy of the current Object.

(Inherited from Object)
MemberwiseClone(Boolean) MemberwiseClone(Boolean) MemberwiseClone(Boolean) MemberwiseClone(Boolean)

创建当前 MarshalByRefObject 对象的浅表副本。Creates a shallow copy of the current MarshalByRefObject object.

(Inherited from MarshalByRefObject)
ObjectInvariant() ObjectInvariant() ObjectInvariant() ObjectInvariant()

提供对 Contract 的支持。Provides support for a Contract.

(Inherited from Stream)
Read(Byte[], Int32, Int32) Read(Byte[], Int32, Int32) Read(Byte[], Int32, Int32) Read(Byte[], Int32, Int32)

将字节从当前缓冲流复制到数组。Copies bytes from the current buffered stream to an array.

Read(Span<Byte>) Read(Span<Byte>) Read(Span<Byte>) Read(Span<Byte>)
ReadAsync(Byte[], Int32, Int32) ReadAsync(Byte[], Int32, Int32) ReadAsync(Byte[], Int32, Int32) ReadAsync(Byte[], Int32, Int32)

从当前流异步读取字节序列,并将流中的位置提升读取的字节数。Asynchronously reads a sequence of bytes from the current stream and advances the position within the stream by the number of bytes read.

(Inherited from Stream)
ReadAsync(Byte[], Int32, Int32, CancellationToken) ReadAsync(Byte[], Int32, Int32, CancellationToken) ReadAsync(Byte[], Int32, Int32, CancellationToken) ReadAsync(Byte[], Int32, Int32, CancellationToken)

从当前流异步读取字节的序列,将流中的位置提升读取的字节数,并监视取消请求。Asynchronously reads a sequence of bytes from the current stream, advances the position within the stream by the number of bytes read, and monitors cancellation requests.

ReadAsync(Memory<Byte>, CancellationToken) ReadAsync(Memory<Byte>, CancellationToken) ReadAsync(Memory<Byte>, CancellationToken) ReadAsync(Memory<Byte>, CancellationToken)
ReadByte() ReadByte() ReadByte() ReadByte()

从基础流中读取一个字节,并返回转换为 int 的该字节;或者如果从流的末尾读取则返回 -1。Reads a byte from the underlying stream and returns the byte cast to an int, or returns -1 if reading from the end of the stream.

Seek(Int64, SeekOrigin) Seek(Int64, SeekOrigin) Seek(Int64, SeekOrigin) Seek(Int64, SeekOrigin)

设置当前缓冲流中的位置。Sets the position within the current buffered stream.

SetLength(Int64) SetLength(Int64) SetLength(Int64) SetLength(Int64)

设置缓冲流的长度。Sets the length of the buffered stream.

ToString() ToString() ToString() ToString()

返回表示当前对象的字符串。Returns a string that represents the current object.

(Inherited from Object)
Write(Byte[], Int32, Int32) Write(Byte[], Int32, Int32) Write(Byte[], Int32, Int32) Write(Byte[], Int32, Int32)

将字节复制到缓冲流,并将缓冲流内的当前位置前进写入的字节数。Copies bytes to the buffered stream and advances the current position within the buffered stream by the number of bytes written.

Write(ReadOnlySpan<Byte>) Write(ReadOnlySpan<Byte>) Write(ReadOnlySpan<Byte>) Write(ReadOnlySpan<Byte>)
WriteAsync(Byte[], Int32, Int32) WriteAsync(Byte[], Int32, Int32) WriteAsync(Byte[], Int32, Int32) WriteAsync(Byte[], Int32, Int32)

将字节序列异步写入当前流,并将流的当前位置提升写入的字节数。Asynchronously writes a sequence of bytes to the current stream and advances the current position within this stream by the number of bytes written.

(Inherited from Stream)
WriteAsync(Byte[], Int32, Int32, CancellationToken) WriteAsync(Byte[], Int32, Int32, CancellationToken) WriteAsync(Byte[], Int32, Int32, CancellationToken) WriteAsync(Byte[], Int32, Int32, CancellationToken)

将字节的序列异步写入当前流,将该流中的当前位置向前移动写入的字节数,并监视取消请求。Asynchronously writes a sequence of bytes to the current stream, advances the current position within this stream by the number of bytes written, and monitors cancellation requests.

WriteAsync(ReadOnlyMemory<Byte>, CancellationToken) WriteAsync(ReadOnlyMemory<Byte>, CancellationToken) WriteAsync(ReadOnlyMemory<Byte>, CancellationToken) WriteAsync(ReadOnlyMemory<Byte>, CancellationToken)
WriteByte(Byte) WriteByte(Byte) WriteByte(Byte) WriteByte(Byte)

将一个字节写入缓冲流的当前位置。Writes a byte to the current position in the buffered stream.

显式界面实现

IDisposable.Dispose() IDisposable.Dispose() IDisposable.Dispose() IDisposable.Dispose()

释放由 Stream 使用的所有资源。Releases all resources used by the Stream.

(Inherited from Stream)

适用于

另请参阅