flex servlet 注意问题

flex与servlet交互数据，有以下几个方面需要注意flex 2010-03-19 18:33:38 阅读55 评论0 字号：大中小
flex与servlet交互数据，有以下几个方面需要注意

参数的传递：

中文乱码的解决

返回值的处理

以下是我今天写的一个执行正常的程序

flex代码如下：

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
<mx:Script>
  <![CDATA[
   import mx.rpc.events.ResultEvent;
   import mx.controls.Alert;
  
   private function doRequest():void{
   this.btn_do.enabled=false;
   var url:String="http://localhost:8080/Test/servlet/BUAA";
   this.sevlet.url=url;
   var param:URLVariables=new URLVariables();
   //这个对象是用来设置url中需要传递的参数,将所传递的参数一一按照如下的格式设置，即可传递到后台服务器
  
   //如下所示传递了两个参数，一个是username,一个是timestamp
   param.username=this.txt.text;
   param.timestamp=(new Date()).toString();
   //////////////////////////////////////////////////////////////////////////////////
  
   this.sevlet.send(param);//
   }
  
      //下面这个函数是服务器处理完毕后flex的处理函数，在下文的标签里有定义
   private function resultHandler(event:ResultEvent):void{
    Alert.show(event.result.user);
    this.btn_do.enabled=true;
   }
  ]]>
</mx:Script>
<mx:HTTPService id="sevlet" resultFormat="e4x" result="resultHandler(event)"/>
<mx:Panel title="测试与servlet后台交互" layout="absolute" width="100%" height="90%">
<mx:VBox>
 
        <mx:Button id="btn_do" label="取得数据" click="doRequest();" fontSize="14"/>
        <mx:TextInput id="txt" text="输入文字" fontSize="14"/>   
         
</mx:VBox>    
    </mx:Panel>
</mx:Application>



Servlet端的代码如下

public void doGet(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  response.setContentType("text/xml;charset=utf-8");
  String para = request.getParameter("username");
  PrintWriter out = response.getWriter();
  String strOut = new String(para.getBytes("ISO8859-1"), "utf-8");
  out.println("<zpa>");
  out.println("<user>"+strOut+"</user>");
  out.println("</zpa>");
  out.flush();
  out.close();
}


对于中文参数的传递，在flex里有以下两个对应的处理函数

   
   //下面的这2个函数是用来处理flex中传递中文参数乱码问题的,一个编码，一个解码
   private function htmlParaEncoding(para:String):String{
    return encodeURIComponent(para);
   }
   private function htmlParaDecoding(para:String):String{
    return decodeURIComponent(para);
   }


不过一般在flex端只需要用编码函数，java中打印结果时使用java.net.URLDecoder.decode方法解码，如下面这个例子

flex代码：

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
    layout="absolute" fontSize="12" xmlns:local="*">
    <mx:TraceTarget/>
    <mx:Style>
        .lab{
           fontWeight: "bold";
           /*color: #FF0000;*/
           fontSize: 15;
        }
    </mx:Style>
    <mx:Script>
        <![CDATA[
        //对提交给后台的参数进行UTF-8的编码处理
        private function httpEncoding(param:String):String{
            return encodeURIComponent(param);
        }
        private function doLogin():void {
            //trace("focusEnabled:"+loading.focusEnabled);
            //this.focusManager.setFocus(user);
            var url:String = "http://localhost:8080/Test/servlet/BUAA";
            var params:URLVariables = new URLVariables();
            //这个user,psw就是传入后台的参数user,jsp就用 request.getParameter("user")来取
            params.user = httpEncoding(user.text);
            params.psw = psw.text;
            var loader:URLLoader = new URLLoader();
            this.configureEventListeners(loader);
            //可以不设置,因为默认是text
            loader.dataFormat = URLLoaderDataFormat.TEXT;
            var request:URLRequest = new URLRequest(url);
            request.data = params;
            try{
                loader.load(request);
            }catch(error:Error){
                trace(error.message);
            }
        }
        private function configureEventListeners(dispatcher:IEventDispatcher):void {
            dispatcher.addEventListener(Event.COMPLETE, completeHandler);
            dispatcher.addEventListener(Event.OPEN, openHandler);
            dispatcher.addEventListener(ProgressEvent.PROGRESS, progressHandler);
            dispatcher.addEventListener(SecurityErrorEvent.SECURITY_ERROR, securityErrorHandler);
            dispatcher.addEventListener(HTTPStatusEvent.HTTP_STATUS, httpStatusHandler);
            dispatcher.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
        }
       private function completeHandler(event:Event):void {
            var loader:URLLoader = URLLoader(event.target);
            trace("--complete..."+event.target.data);
            //var dataXML:XML = XML(event.target.data);
            //trace(dataXML.toXMLString());
            btn_btn.enabled=true;
        }

        private function openHandler(event:Event):void {
            trace("openHandler: " + event);
            //this.focusManager.setFocus(loading);
            btn_btn.enabled=false;
        }

        private function progressHandler(event:ProgressEvent):void {
            trace("progressHandler loaded:" + event.bytesLoaded + " total: " + event.bytesTotal);
        }

        private function securityErrorHandler(event:SecurityErrorEvent):void {
            trace("securityErrorHandler: " + event);
        }

        private function httpStatusHandler(event:HTTPStatusEvent):void {
            trace("httpStatusHandler: " + event);
        }

        private function ioErrorHandler(event:IOErrorEvent):void {
            trace("ioErrorHandler: " + event);
        }
        ]]>
    </mx:Script>
   
    <mx:Panel title="欢迎登录WAP管理系统：" width="307" height="189" layout="absolute" verticalAlign="top" horizontalCenter="-10.5" verticalCenter="-9">
        <mx:Label x="32" y="25" text="登录口令:" width="59"/>
        <mx:TextInput id="user" x="99" y="23" width="147"/>
        <mx:Label x="32" y="53" text="登录密码:" width="59"/>
        <mx:TextInput id="psw" x="99" y="51" displayAsPassword="true" width="147"/>
        <mx:ControlBar alpha="1">
            <mx:Button id="btn_btn" x="58" y="92" label="确 定" click="this.doLogin();"/>
            <mx:Button x="162" y="92" label="取 消"/>
            <mx:Label x="0" y="129" text="Powered by Keren" textAlign="right"/>
        </mx:ControlBar>
    </mx:Panel>
</mx:Application>



java代码

  String usr = java.net.URLDecoder.decode(request.getParameter("user"), "UTF-8");
  System.out.println("取得传入的参数:"+usr);
  String psw = java.net.URLDecoder.decode(request.getParameter("psw"), "UTF-8");
  System.out.println("取得传入的参数:"+psw);
  out.flush();
  out.close();


此外，在网上也参考到一些不错的文章，摘录如下：

 
http://www.cnblogs.com/dannyr/archive/2004/11/24/68026.html

原文

情况：

Flex默认使用的都是utf-8编码，包括Get，Post等方法。而Tomcat服务器端接收request对象默认是8859_1 编码，添加Tomcat的request Filter用request.setCharacterEncoding("utf-8"); 来设置，这个方法属于Tomcat设置和Flex无关，暂不讨论！

flex ->Jsp：

有2种情况 //我试验第2种情况，测试通过

情况一、MXML源代码文件中写入的中文字符：

Flex使用 System.useCodepage = true;即使用本地操作系统编码（GBK） 设置Flex的处理编码。Jsp中用依然用ISO_8859_1 编码来处理，并转化为GBK 。这样Jsp可以正确解释Flex传递的中文字符。 这个时候可以认为Flex对mxml源代码文件进行编译时候，源代码中的中文字符已经混乱了，所以要加上System.useCodepage = true;语句， 按GBK编码将中文字符从Flex发送到Tomcat。

同时Tomcat中Jsp应该按GBK 重新编码

String categoryID = request.getParameter("categoryID");

String strOut = new String(categoryID.getBytes("ISO8859-1 "), "GBK ");

System.out.println("categoryID="+categoryID);

System.out.println("categoryID="+strOut);

情况二、Flex运行时候由输入框输入的中文字符

这个时候输入框输入的中文字符是一定为UTF-8编码的，所以Flex中System.useCodepage = false;或者不设置，就默认utf-8编码格式传递数据，而Tomcat中Jsp使用下面语句按UTF-8来重新编码

String categoryID = request.getParameter("categoryID");

String strOut = new String(categoryID.getBytes("ISO8859-1"), "utf-8");

System.out.println("categoryID="+categoryID);

System.out.println("categoryID="+strOut);

Jsp->Flex：

Jsp页面用页面指令<%@ page contentType="text/html;charset=utf-8"%> 设置，返回结果是utf-8编码，Flex接收后成功解释并正确显示。



 
原文：http://haitao-love-u.blog.sohu.com/116743431.html

通常办法在jsp页面中，加入<% request.setCharacterEncoding("utf-8"); %>，flex默认编码是utf-8。然而，如果问题没有解决，依旧是乱码的话，那么，打开你的tomcat目录下的conf/server.xml文件，观察： <Connector port="8080" protocol="HTTP/1.1"

               maxThreads="150" connectionTimeout="20000"

               redirectPort="8443" URIEncoding="UTF-8"/>，若没有URIEncoding="UTF-8"，添加进去，这样问题就圆满解决了。顺便说下，mysql数据库编码也是utf-8



原文：http://java-007.iteye.com/blog/381617

最近看一些文档,总结了一些<mx:HTTPService>给后台传递参数的方法,列举如下:

方法1:采用URLVariables对象

<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml"
     layout="absolute" fontSize="12"
    >
    <mx:Script>
        <![CDATA[
            import mx.controls.Alert;
            import mx.rpc.events.ResultEvent;
            //对提交给后台的参数进行UTF-8的编码处理
            private function httpEncoding(param:String):String{
                return encodeURIComponent(param);
            }
            private function httpEncoding0(param:String):String{
                return param;//encodeURI(param);
            }
            private function doRequest():void{
                btn_do.enabled=false;
                var url:String = "http://localhost:8600/grid.jsp";
                //以下那样写后台会乱码,不管是否做URI编码转换
                //url += "?user="+httpEncoding0("用户名");
                //url += "&psw="+httpEncoding0("密码");
                //trace(url);
                srv.url = url;
                //srv.send();
                //以下这样写正常
                var params:URLVariables = new URLVariables();
                //这个user,psw就是传入后台的参数user,jsp就用 request.getParameter("user")来取
                params.user = httpEncoding("用户名");
                params.psw = httpEncoding("密码");
                srv.send(params);           
            }
            private function resultHandler(event:ResultEvent):void{
                Alert.show("与后台交互结束,前台开始取得的数据...","提示信息");
                btn_do.enabled=true;
            }
        ]]>
    </mx:Script>
    <mx:HTTPService id="srv" result="resultHandler(event);"/>
    <mx:Panel title="测试与jsp后台交互" layout="absolute" width="100%" height="90%">
        <mx:Button id="btn_do" label="取得数据" click="doRequest();"/>
        <mx:Spacer height="1"/>
        <mx:DataGrid dataProvider="{srv.lastResult.catalog.product}" width="100%" height="100%" y="28"/>    
    </mx:Panel>
</mx:Application>
方法2:采用<mx:request/>,同时也演示了mx:State的用法,[来自网上]



<?xml version="1.0" encoding="utf-8"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute">
    <mx:states>
        <mx:State name="Logged In">
            <mx:SetProperty target="{panel1}" name="width" value="95%"/>
            <mx:SetProperty target="{panel1}" name="height" value="95%"/>
            <mx:RemoveChild target="{password}"/>
            <mx:RemoveChild target="{username}"/>
            <mx:RemoveChild target="{label1}"/>
            <mx:RemoveChild target="{Submit}"/>
            <mx:RemoveChild target="{label2}"/>
            <mx:SetProperty target="{panel1}" name="title" value="Members Section"/>
            <mx:AddChild relativeTo="{panel1}" position="lastChild">
                <mx:Label x="10" y="10" text="Welcome to the Members Section!"/>
            </mx:AddChild>
            <mx:AddChild relativeTo="{panel1}" position="lastChild">
                <mx:Label x="10" y="36" text="Here you can do great things, like join the forums @ Viper Creations!"/>
            </mx:AddChild>
            <mx:AddChild relativeTo="{panel1}" position="lastChild">
                <mx:Label x="10" y="62" text="Label"/>
            </mx:AddChild>
        </mx:State>
    </mx:states>
    <mx:Script>
        <![CDATA[
            import mx.rpc.events.ResultEvent;
           
        ]]>
    </mx:Script>
    <mx:Script>
   

<![CDATA[

private function checkLogin(evt:ResultEvent):void
{

    if(evt.result.loginsuccess == "yes")

    {

    currentState = "Logged In";

    }

    if(evt.result.loginsuccess == "no")

    {
       
        mx.controls.Alert.show(''Invalid username/password'');

    }       
}

]]>

</mx:Script>
    <mx:HTTPService id="login_user" result="checkLogin(event)" showBusyCursor="true" method="POST" url="http://www.vipercreations.com/site_admin/login.php" useProxy="false">
        <mx:request xmlns="">
            <username>
                {username.text}
            </username>
            <password>
                {password.text}
            </password>
        </mx:request>
    </mx:HTTPService>
   
    <mx:Panel resizeEffect="Resize" width="250" height="200" layout="absolute" title="Login System" horizontalCenter="0" verticalCenter="-2" id="panel1">
        <mx:Label x="10" y="10" text="Username:" id="label1"/>
        <mx:TextInput x="10" y="36" id="username"/>
        <mx:Label x="10" y="66" text="Password:" id="label2"/>
        <mx:TextInput x="10" y="92" id="password" displayAsPassword="true"/>
        <mx:Button x="10" y="122" label="Submit" id="Submit" click="login_user.send();"/>
    </mx:Panel>
   
</mx:Application>

评论

1 楼 tianhaos 2011-01-26  

楼主 请教一下 我用你的例子 报 “-由于“HTTPService”声明未实现“mx.core.IUIComponent”，它必须包含在 <Declarations> 标签中。”错误，请问怎么解决啊 ！！！谢谢了！！！