Flex获取操作XML示例

Flex获取操作XML示例

 

些示例演示了FLEX对XML的一般操作

操作符说明：

    /****** ".","[]","..","@" 四个常用的E4X操作符 ******/
    //使用"."操作符查询节点,得到第一个子节点,使用"[]"访问指定索引的节点 
    //使用".."操作符访问所有以该标签命名的节点，而忽略节点的上下关系
    //使用"@"操作符访问节点属性
代码段readXml，changeXml有详细用法

 

1、XML文件

文件一  mybook.xml:

 <?xml version="1.0" ?> <books> <category name="RIA"> <book name="flex tutorial" price="30" author="adobe"> </book> <book name="air tutorial" price="40" author="adobe"> </book> </category> <category name="Java"> <book name="java tutorial" price="50" author="sun"> </book> </category> </books>

文件二 myxml.xml

 <?xml version="1.0" ?> <items> <item> <name>百度</name> <url>http://www.baidu.com</url> <image>assets/baidu.gif</image> </item> <item> <name>新浪</name> <url>http://www.sina.com</url> <image>assets/sina.gif</image> </item> <item> <name>开心网</name> <url>http://www.kaixin001.com</url> <image>assets/kaixin001.gif</image> </item> <item> <name>QQ邮箱</name> <url>http://mail.qq.com</url> <image>assets/qqmail.gif</image> </item> <item> <name>谷歌</name> <url>http://www.google.com.cn</url> <image>assets/google.gif</image> </item> </items>

2、Flex部分代码

<?xml version="1.0" encoding="utf-8"?> <mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute"> <mx:Script> <!--[CDATA[ import mx.collections.XMLListCollection; import mx.collections.ArrayCollection; import mx.rpc.events.ResultEvent; import mx.rpc.http.HTTPService; [Bindable] private var textareaTxt:String = ""; [Bindable] private var list:ArrayCollection; [Bindable] private var xmlList:XMLList; //----------------------------------------------------------- // 创建简单XML部分 //----------------------------------------------------------- private function varCreateXml():void { var myText:String = "测试"; var str:String = "<test><elelment>" + myText + "</elelment></test>"; var testXmlObj:XML = new XML(str); trace(testXmlObj.toXMLString()); } //----------------------------------------------------------- // HttpService部分 //----------------------------------------------------------- private function httpServiceGetXml():void { var httpservice:HTTPService = new HTTPService(); //httpservice.url = "http://localhost:2286/myxml.xml"; httpservice.url = "http://localhost:2286/mybook.xml"; httpservice.useProxy = false; //httpservice.resultFormat = "array"; //结果要转换为ArrayCollection应用到List,DataGrid时使用 httpservice.resultFormat = "e4x"; //Tree控件 httpservice.addEventListener(ResultEvent.RESULT,onHttpServiceResultHandler); httpservice.send(); } private function onHttpServiceResultHandler(event:ResultEvent):void { var strresult:String = event.result.toString(); var externalXML:XML = new XML(strresult); trace(externalXML.toXMLString()); //转换XML为ArrayCollection显示到数据容器中部分, 此时httpService的resultFormat需要为"array" //list = event.result[0].items.item; //转移为XMLListCollection,应用到Tree xmlList = event.result.category; } //----------------------------------------------------------- // URLLoader部分 //----------------------------------------------------------- private function urlLoaderGetXml():void { var urlLoader:URLLoader = new URLLoader(); var urlRequest:URLRequest = new URLRequest("myxml.xml"); urlLoader.load(urlRequest); urlLoader.addEventListener(Event.COMPLETE,onUrlLoaderHandler); } private function onUrlLoaderHandler(event:Event):void { var urlLoader2:URLLoader = event.target as URLLoader; if(urlLoader2 != null) { var externalXML:XML = new XML(urlLoader2.data); trace(externalXML.toXMLString()); //readXml(externalXML); //changeXml(externalXML); } else { trace("urlLoader2 is not a URLLoader!"); } } //----------------------------------------------------------- // 操作XML部分 //----------------------------------------------------------- private function readXml(xml:XML):void { if(xml == null) return; /****** ".","[]","..","@" 四个常用的E4X操作符 ******/ //使用"."操作符查询节点,得到第一个子节点,使用"[]"访问指定索引的节点 writeMsg(xml.item[0]); //使用".."操作符访问所有以该标签命名的节点，而忽略节点的上下关系 writeMsg(xml..name); //使用"@"操作符访问节点属性 writeMsg(xml.item[0].@name); writeMsg(xml.item[0].name.@url); //过滤,只显示name为"百度"的节点。属性和节点都可过滤 writeMsg(xml.item.(name=="百度")); //修改 writeMsg(xml.item[0].(name="百度一下就知道")); } private function changeXml(xml:XML):void { if(xml == null) return; /****** 修改操作 XML对象包括修改，添加和删除操作******/ //使用insertChildBefore和insertChildAfter方法在某一位置添加元素/节点，appendChild和prependChild方法在最前和最后添加元素/节点 xml.insertChildAfter(xml.item[0],<item name="站点insertChildAfter"/>); xml.insertChildBefore(xml.item[0],<item name="站点insertChildBefore"/>); xml.appendChild(<item name="站点appendChild"/>); xml.prependChild(<item name="站点prependChild"/>); //writeMsg(xml); //添加、修改属性 xml.item[0].@date="20100721"; //writeMsg(xml); //添加、修改XML对象 xml.item[0].name = "prependChild"; xml.item[0].url = "http://www.prependChild.com"; writeMsg(xml); writeMsg("============"); //删除节点、属性等 delete xml.item[0].@date; delete xml.item[0].name; delete xml.item[0].url.text()[0]; writeMsg(xml); } private function writeMsg(s:String):void { txtarea.text += s + "\n"; } ]]--> </mx:Script> <mx:Button x="10" y="10" label="变量创建XML" click="varCreateXml()"/> <mx:Button x="138" y="10" label="HttpService获取XML" click="httpServiceGetXml()"/> <mx:Button x="318" y="10" label="UrlLoader获取XML" click="urlLoaderGetXml()"/> <mx:TextArea x="10" y="117" id="txtarea" width="387" height="284"/> <mx:List x="418" y="117" id="dataList" width="188" height="134" dataProvider="{list}"></mx:List> <mx:DataGrid x="418" y="259" id="dataGrid" width="406" dataProvider="{list}"> <mx:columns> <mx:DataGridColumn headerText="Column 1" dataField="name"/> <mx:DataGridColumn headerText="Column 2" dataField="url"/> <mx:DataGridColumn headerText="Column 3" dataField="image"/> </mx:columns> </mx:DataGrid> <mx:Tree x="625" y="51" width="199" height="200" dataProvider="{xmlList}" labelField="@name"/> </mx:Application>