Flex FTP文件上传

　　Flex FTP文件上传原理就是利用Flex Socket组件与FTP服务器进行网络通讯并根据FTP协议进行指令发生、接收，数据的传输和接收。本文指的是Flex web应用的FTP文件上传，具体实现有下述3个工作：
　　1）上传文件选择、加载，可以使用Flex的FileRefrence组件；
　　2）socket创建、连接、ftp用户登录信息的验证；
　　3）文件数据发送；
　　先假设要上传的文件名称为：demo.doc, 该上传的文件内容为fileData，下述为FTP文件上传的核心类。 package fileupload {     import flash.events.Event;     import flash.events.IEventDispatcher;     import flash.events.IOErrorEvent;     import flash.events.ProgressEvent;     import flash.events.SecurityErrorEvent;     import flash.net.FileReference;     import flash.net.Socket;     import flash.utils.ByteArray;     import flash.utils.clearInterval;     import flash.utils.setInterval;       publicclass FtpFileUpDownload     {        privatevar ftpSocket:Socket;        privatevar ftpResponce:String;        privatevar dataSocket:Socket;        privatevar dataResponse:String;        privatevar clientIP:String;        privatevar clientPort:uint;        privatevar canceled:Boolean = false;        privatevar dispatcher:IEventDispatcher;        privatevar fileName:String;        privatevar fileData:ByteArray;        privatevar _isAnonymous:Boolean = false;        privatevar _userName:String;        privatevar _serverIP:String;        privatevar _userPwd:String;        privatevar _userDir:String;        privatevar _serverPort:uint = 21;        privatevar intervalID:int;        //        publicfunction FtpFileUpDownload(dispatcher:IEventDispatcher)        {            this.dispatcher = dispatcher;        }          /**         * isAnonymous, FTP 是否允许匿名访问,默认为false
　　*/
　　publicfunctionget isAnonymous():Boolean{
　　return _isAnonymous;
　　}
　　publicfunctionset isAnonymous(value:Boolean):void{
　　_isAnonymous = value;
　　}
　　publicfunctionget userName():String{
　　return _userName;
　　}
　　publicfunctionset userName(value:String):void{
　　_userName = value;
　　}
　　publicfunctionget serverIP():String{
　　return _serverIP;
　　}
　　publicfunctionset serverIP(value:String):void{
　　_serverIP = value;
　　}
　　publicfunctionget userPwd():String{
　　return _userPwd;
　　}
　　publicfunctionset userPwd(value:String):void{
　　_userPwd = value;
　　}
　　/**
　　* userDir, FTP 用户上传目录
　　*/
　　publicfunctionget userDir():String{
　　return _userDir;
　　}
　　publicfunctionset userDir(value:String):void{
　　_userDir = value;
　　}
　　publicfunctionget serverPort():uint{
　　return _serverPort;
　　}
　　publicfunctionset serverPort(value:uint):void{
　　_serverPort = value;
　　}
　　/**
　　* upload file, data is null is not allowed.
　　*/
　　publicfunction upload(data:ByteArray, fileName:String):void{
　　this.fileName = fileName;
　　this.fileData = data;
　　if(data==null){
　　dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,"Data is null is not allowed!"));
　　return;
　　}
　　if(!check()) return;
　　connect();
　　}
　　privatefunction check():Boolean{            var blnResult:Boolean = true;            if(!isAnonymous){               if(StringUtil.isEmpty(userName) || StringUtil.isEmpty(userPwd)){//                   dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,                      "请输入用户名和口令!"));
　　blnResult = false;
　　}
　　}
　　if(StringUtil.isEmpty(serverIP)){
　　dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,
　　"请输入FTP服务器IP地址!"));
　　blnResult = false;
　　}
　　return blnResult;
　　}
　　privatefunction connect():void{
　　ftpSocket = newSocket(serverIP, serverPort);
　　ftpSocket.addEventListener(ProgressEvent.SOCKET_DA TA, ftpSocketDataHandle);      ftpSocket.addEventListener(SecurityErrorEvent.SECU RITY_ERROR,ftpSocketSecurityErrorHandle);
　　ftpSocket.addEventListener(IOErrorEvent.IO_ERROR,f tpIOErrorHandle);
　　}
　　privatefunction ftpIOErrorHandle(evt:IOErrorEvent):void {
　　dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,evt. text));
　　}
　　privatefunction ftpSocketSecurityErrorHandle(evt:SecurityErrorEven t):void {
　　dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,evt. text));
　　}
　　privatefunction dataSocketSecurityErrorHandle(evt:SecurityErrorEve nt):void {
　　dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,evt. text));
　　}
　　//发送ftpsocket ftp 指令        privatefunction sendCommand(arg:String):void {            arg +="\n";            var content:ByteArray = new ByteArray();            content.writeMultiByte(arg,"gb2312");            ftpSocket.writeBytes(content);            ftpSocket.flush();        }                privatefunction dataIOErrorHandle(evt:IOErrorEvent):void {            dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,evt. text));        }                privatefunction ftpSocketDataHandle(evt:ProgressEvent):void{            ftpResponce = ftpSocket.readUTFBytes(ftpSocket.bytesAvailable);            var serverResponse:String =ftpResponce.substr(0, 3);            if(ftpResponce.indexOf('227')>-1){               //取得使用者的ip位置               var temp:Object = ftpResponce.substring(ftpResponce.indexOf("(")+1 ,ftpResponce.indexOf(")"));               var upLoadSocket_temp:Object = temp.split(",");               clientIP = upLoadSocket_temp.slice(0,4).join(".");               clientPort = parseInt(upLoadSocket_temp[4])*256+                   int(upLoadSocket_temp[5]);                              //创建上传的ftp连接               dataSocket = newSocket(clientIP,clientPort);               dataSocket.addEventListener(ProgressEvent.SOCKET_D ATA, receiveData);               dataSocket.addEventListener(IOErrorEvent.IO_ERROR, dataIOErrorHandle);                dataSocket.addEventListener(SecurityErrorEvent.SEC URITY_ERROR,dataSocketSecurityErrorHandle);               //upload file               sendCommand("STOR "+this.fileName);            }            switch(serverResponse){               case"150":   //开始文件传输                   curPos = 0;                   intervalID = setInterval(sendData,30);                   break;               case"220": //FTP连接就绪                   sendCommand("USER "+this.userName);                   break;               case"331"://用户名正确，请继续输入口令                   sendCommand("PASS "+this.userPwd);                   break;               case"230"://登入成功                   //指定下载文件的类型，I是二进位文件，A是字元文件                               sendCommand("TYPE A");//设定TYPE为ASCII                   sendCommand("TYPE I");//设定上传的编码为8-bit binary                   if(!StringUtil.isEmpty(userDir))   //设定FTP 上传目录                      sendCommand("CWD "+userDir);                   sendCommand("PASV");//passive模式                   break;               case"250" ://资料夹切换成功                   break;               case"226"://关闭数据连接。请求的文件操作成功（比如，文件传输或文件终止)                   ftpSocket.close();                   dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.COMPLETED) );                   break;               case"227" : //Entering Passive Mode (h1,h2,h3,h4,p1,p2).                   break;               case"530":   //530 Login incorrect                   dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,"用户名或者密码有误!"));
　　break;
　　case"421":
　　dispatcher.dispatchEvent(new FileUpDownloadEvent(FileUpDownloadEvent.ERROR,"连接超时!"));
　　break;
　　default:
　　}
　　trace("ftp response: "+ftpResponce);
　　}
　　privatevar curPos:int = 0;
　　privatefunction sendData():void{
　　var fileContents:ByteArray =this.fileData;
　　var fileSize:uint = this.fileData.length;
　　var chunk:uint = 1024*2;            //var pos:int = 0;            if(curPos+chunk>fileSize){               dataSocket.close();               clearInterval(intervalID);               return;            }            dataSocket.writeBytes(fileContents,curPos,chunk);            dataSocket.flush();            curPos+=chunk;        }                privatefunction receiveData():void{            var responce:String = dataSocket.readUTFBytes(dataSocket.bytesAvailable) ;            trace("dataSocket response: "+responce);        }     } } FTP文件上传事件代码： package whh.flex.controls.fileupload {     import flash.events.Event;     publicclassFileUpDownloadEventextends Event     {        publicstaticconst ERROR:String       = "FILE_UPLOAD_ERROR";        publicstaticconst COMPLETED:String   = "FILE_UPLOAD_COMPLETED";        publicstaticconst CANCEL:String      = "FILE_UPLOAD_CANCEL";        //        privatevar _message:String;        privatevar _data:Object;        //        publicfunctionFileUpDownloadEvent(type:String, message:String = null)        {            super(type,true);            this._name = name;            this._message = message;        }        //        publicfunctionget message():String{            return _message;        }        publicfunctionset message(value:String):void{            _message = value;        }     } } 则Application中要进行FTP文件上传，可简单codeing为（假设FTPFileUpDownload实例为ftpFile）：
　　ftpFile.upload(fileData, "demo.doc")
　　当然为了侦听ftp上传是否出错、完成，需要侦听FileUpDownloadEvent的Error和Complete事件。