AS3 Telnet示例不讀取響應

Question

我正在測試我從adobe獲取的示例，即TelnetSocket示例。這是代碼：

TelnetSocket.mxml：

<?xml version="1.0" encoding="utf-8"?> 
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" 
    layout="vertical"> 

    <mx:Script> 
     <![CDATA[ 
      import com.example.programmingas3.socket.Telnet; 
      private var telnetClient:Telnet; 
      private function connect():void { 
       telnetClient = new Telnet(serverName.text, int(portNumber.text), output); 
       console.title = "Connecting to " + serverName.text + ":" + portNumber.text; 
       console.enabled = true; 
      } 
      private function sendCommand():void { 
       var ba:ByteArray = new ByteArray(); 
       ba.writeMultiByte(command.text + "\n", "UTF-8"); 
       telnetClient.writeBytesToSocket(ba); 
       command.text = ""; 
      } 
     ]]> 
    </mx:Script> 

    <mx:Label id="title" text="Telnet Socket Example" fontSize="24" fontStyle="italic" /> 
    <mx:Label id="subtitle" text="From Programming ActionScript 3.0, Chapter 22: Networking and communication" fontSize="12" /> 

    <mx:ApplicationControlBar width="100%"> 
     <mx:Label text="Server:" /> 
     <mx:TextInput id="serverName" width="100%" /> 
     <mx:Spacer /> 
     <mx:Label text="Port:" /> 
     <mx:TextInput id="portNumber" text="23" textAlign="right" maxChars="5" restrict="0-9" /> 
     <mx:Spacer /> 
     <mx:Button label="Login" click="connect();" /> 
    </mx:ApplicationControlBar> 

    <mx:Spacer /> 

    <mx:Panel id="console" enabled="false" width="100%" height="100%" paddingTop="10" paddingBottom="10" paddingLeft="10" paddingRight="10"> 
     <mx:TextArea id="output" editable="false" width="100%" height="100%" fontFamily="Courier New" /> 
     <mx:ControlBar> 
      <mx:Label text="Command:" /> 
      <mx:TextInput id="command" width="100%" enter="sendCommand();" /> 
      <mx:Button label="Send" click="sendCommand();" /> 
     </mx:ControlBar> 
    </mx:Panel> 

</mx:Application> 

COM \例子\ programmingas3 \插座\ Telnet.as：

package com.example.programmingas3.socket { 
    import flash.events.*; 
    import flash.net.Socket; 
    import flash.system.Security; 
    import flash.utils.ByteArray; 
    import flash.utils.setTimeout; 

    import mx.controls.TextArea; 
    import mx.core.UIComponent; 

    public class Telnet extends UIComponent{ 
     private const CR:int = 13; // Carriage Return (CR) 
     private const WILL:int = 0xFB; // 251 - WILL (option code) 
     private const WONT:int = 0xFC; // 252 - WON'T (option code) 
     private const DO:int = 0xFD; // 253 - DO (option code) 
     private const DONT:int = 0xFE; // 254 - DON'T (option code) 
     private const IAC:int = 0xFF; // 255 - Interpret as Command (IAC) 

     private var serverURL:String; 
     private var portNumber:int; 
     private var socket:Socket; 
     private var ta:TextArea; 
     private var state:int = 0; 

     public function Telnet(server:String, port:int, output:TextArea) { 
      // set class variables to the values passed to the constructor. 
      serverURL = server; 
      portNumber = port; 
      ta = output; 

      // Create a new Socket object and assign event listeners. 
      socket = new Socket(); 
      socket.addEventListener(Event.CONNECT, connectHandler); 
      socket.addEventListener(Event.CLOSE, closeHandler); 
      socket.addEventListener(ErrorEvent.ERROR, errorHandler); 
      socket.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler); 
      socket.addEventListener(ProgressEvent.SOCKET_DATA, dataHandler); 

      // Load policy file from remote server. 
      Security.loadPolicyFile("http://" + serverURL + "/crossdomain.xml"); 
      // Attempt to connect to remote socket server. 
      try { 
       msg("Trying to connect to " + serverURL + ":" + portNumber + "\n"); 
       socket.connect(serverURL, portNumber); 
      } catch (error:Error) { 
       /* 
        Unable to connect to remote server, display error 
        message and close connection. 
       */ 
       msg(error.message + "\n"); 
       socket.close(); 
      } 
     } 

     /** 
     * This method is called if the socket encounters an ioError event. 
     */ 
     public function ioErrorHandler(event:IOErrorEvent):void { 
      msg("Unable to connect: socket error.\n"); 
     } 

     /** 
     * This method is called by our application and is used to send data 
     * to the server. 
     */ 
     public function writeBytesToSocket(ba:ByteArray):void { 
      socket.writeBytes(ba); 
      socket.flush(); 
     } 

     private function connectHandler(event:Event):void { 
      if (socket.connected) { 
       msg("connected...\n"); 
      } else { 
       msg("unable to connect\n"); 
      } 
     } 

     /** 
     * This method is called when the socket connection is closed by 
     * the server. 
     */ 
     private function closeHandler(event:Event):void { 
      msg("closed...\n"); 
     } 

     /** 
     * This method is called if the socket throws an error. 
     */ 
     private function errorHandler(event:ErrorEvent):void { 
      msg(event.text + "\n"); 
     } 

     /** 
     * This method is called when the socket receives data from the server. 
     */ 
     private function dataHandler(event:ProgressEvent):void { 
      var n:int = socket.bytesAvailable; 
      // Loop through each available byte returned from the socket connection. 
      while (--n >= 0) { 
       // Read next available byte. 
       var b:int = socket.readUnsignedByte(); 
       switch (state) { 
        case 0: 
         // If the current byte is the "Interpret as Command" code, set the state to 1. 
         if (b == IAC) { 
          state = 1; 
         // Else, if the byte is not a carriage return, display the character using the msg() method. 
         } else if (b != CR) { 
          msg(String.fromCharCode(b)); 
         } 
         break; 
        case 1: 
         // If the current byte is the "DO" code, set the state to 2. 
         if (b == DO) { 
          state = 2; 
         } else { 
          state = 0; 
         } 
         break; 
        // Blindly reject the option. 
        case 2: 
         /* 
          Write the "Interpret as Command" code, "WONT" code, 
          and current byte to the socket and send the contents 
          to the server by calling the flush() method. 
         */ 
         socket.writeByte(IAC); 
         socket.writeByte(WONT); 
         socket.writeByte(b); 
         socket.flush(); 
         state = 0; 
         break; 
       } 
      } 
     } 

     /** 
     * Append message to the TextArea component on the display list. 
     * After appending text, call the setScroll() method which controls 
     * the scrolling of the TextArea. 
     */ 
     private function msg(value:String):void { 
      ta.text += value; 
      ta.dispatchEvent(new Event(Event.CHANGE)); 
      setTimeout(setScroll, 100); 
     } 

     /** 
     * Scroll the TextArea component to its maximum vertical scroll 
     * position so that the TextArea always shows the last line returned 
     * from the server. 
     */ 
     public function setScroll():void { 
      ta.verticalScrollPosition = ta.maxVerticalScrollPosition; 
     } 
    } 
} 

我mxmlc的路徑編譯它\到\ file \ TelnetSocket.mxml並編譯好，但是當我測試它時，它只是說：「嘗試連接到...」並保持在那裏。我試圖連接到公共telnet BBS服務器，如「telnet：//fix.no」，我打開wireshark，當我點擊swf上的「登錄」按鈕時，日誌中顯示「試圖連接到...」那裏，但是在Wireshark上，我可以看到如果從控制檯telneting，我會看到telnet響應。

我測試了多個服務器，所有服務器都有相同的結果。

那麼可能會發生什麼導致這不讀取服務器的響應？

Answer 1

該示例正常工作。它必須是客戶端（您的計算機）或服務器（telnet服務器）上的防火牆相關問題。