具有错误处理功能的Powershell TCP客户端

Question

我需要有关Powershell TCP客户端的帮助，该客户端可以监视服务器何时关闭连接。这段代码的起点是here，看起来像这样：

## Connect-Computer.ps1 
## Interact with a service on a remote TCP port 
param( 
    [string] $remoteHost = "localhost", 
    [int] $port = 23
     ) 

try
{
    ## Open the socket, and connect to the computer on the specified port 
    write-host "Connecting to $remoteHost on port $port"
    $socket = new-object System.Net.Sockets.TcpClient($remoteHost, $port) 
    if($socket -eq $null) { return; } 

    $stream = $socket.GetStream() 
    $writer = new-object System.IO.StreamWriter($stream) 

    $buffer = new-object System.Byte[] 1024 
    $encoding = new-object System.Text.AsciiEncoding 

    while($true) 
    { 
       ## Allow data to buffer for a bit 
       start-sleep -m 500 

       ## Read all the data available from the stream, writing it to the 
       ## screen when done. 
       while($stream.DataAvailable)  
       {  
          $read = $stream.Read($buffer, 0, 1024)    
          write-host -n ($encoding.GetString($buffer, 0, $read))  
       } 

       ## Read the user's command, quitting if they hit ^D 
       $command = read-host

       ## Write their command to the remote host      
       $writer.WriteLine($command) 
       $writer.Flush() 
    } 
}
finally
{
    ## Close the streams 
    $writer.Close() 
    $stream.Close()
}

问题是当服务器关闭端口时，客户端继续等待。如何使用缓冲读取但仍检查端口是否仍然打开？几分钟后，我不需要立即知道端口是否关闭。

在此先感谢您的帮助。