Flex xml的实用操作
XML类包含用于处理XML对象的工作方法和属性。 XML类（以及XMLList，命名空间和QName类）基于ECMAScript中定义的XML（E4X）规范（ECMA - 357第2版）标准，实现了强大的XML处理在。使用toXMLString（）方法返回的XML对象的字符串表示不论XML对象具有简单内容还是复杂内容。
但是flex的xml操作还不支持xquery等简便、强大的查询操作，但是对于一般的xml结点读取、属性读取、结点查找、属性查找、结点遍历等还是完全可以胜任。
本文提供了一个xml操作的实用Demo，主要有下述3部分内容：
1）构建xml；
2）xml结点读取、属性读取、结点遍历等；
3）用户可以利用..先得到所有结点列表xmllist，然后遍历该xmllist查找任何元素、结点。
| <?xml version="1.0" encoding="utf-8"?> <!--xml 操作demo--> <s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" xmlns:s="library://ns.adobe.com/flex/spark" xmlns:mx="library://ns.adobe.com/flex/mx" width="800" height="600" creationComplete="init()" fontSize="11"> <s:layout> <s:BasicLayout/> </s:layout>
<fx:Script> <![CDATA[ protected function btnQuery_clickHandler(event:MouseEvent):void { var xmllist:XMLList = employees..employee; //列举所有员工信息
txtOpreate.text=""; for each(var item:XML in xmllist){ //遍历员工信息，看是否有匹配的zip if(item.address.zip==txtZip.text){ txtOpreate.text = item.toXMLString(); break; } } } ]]> </fx:Script>
<fx:Script> <![CDATA[ private var employees:XML; // protected function init():void{ //构建XML employees = <employees> <employee ssn="123-123-1234"> <name first="John" last="Doe"/> <address> <street>11 Main St.</street> <city>San Francisco</city> <state>CA</state> <zip>98765</zip> </address> </employee> <employee ssn="789-789-7890"> <name first="Mary" last="Roe"/> <address> <street>99 Broad St.</street> <city>Newton</city> <state>MA</state> <zip>01234</zip> </address> </employee> </employees>; //显示xml XML.prettyIndent = 2; //设置xml缩进量 txtSrc.text = employees.toXMLString(); }
protected function btnShow_clickHandler(event:MouseEvent):void { var output:String = ""; //employees.employee[0].address.zip, 98765 output+="employees.employee[0].address.zip: "+employees.employee[0].address.zip+"\r\n\r\n"; //employees.employee[1].@ssn, 789-789-7890 output+="employees.employee[1].@ssn: "+employees.employee[1].@ssn+"\r\n\r\n"; //employees.employee.name, <name first="John" last="Doe"/> //<name first="Mary" last="Roe"/> output+="employees.employee.name: "+employees.employee.name+"\r\n\r\n"; //employees..zip[0], 98765 output+="employees..zip[0]: "+employees..zip[0]+"\r\n\r\n"; //employees..@ssn[1], 789-789-7890 output+="employees..@ssn[1]: "+employees..@ssn[1]+"\r\n\r\n"; //employees..name, <name first="John" last="Doe"/> //<name first="Mary" last="Roe"/> output+="employees..name: "+employees..name+"\r\n\r\n"; //employees.employee[0].address.*, <street>11 Main St.</street> //<city>San Francisco</city> //<state>CA</state> //<zip>98765</zip> output+="employees.employee[0].address.*: "+employees.employee[0].address.*+"\r\n";
txtOpreate.text = output;
} ]]> </fx:Script>
<fx:Declarations> <!-- 将非可视元素（例如服务、值对象）放在此处 --> </fx:Declarations> <s:Button id="btnShow" click="btnShow_clickHandler(event)" label="展示XML操作信息" left="3" top="3"/>
<s:TextInput id="txtZip" top="3" width="70" right="80" toolTip="请输入员工的ZIP" text="01234"/> <s:Button id="btnQuery" top="3" width="70" right="3" toolTip="查找" label="查找" click="btnQuery_clickHandler(event)"/> <mx:HDividedBox id="dividedbox" top="30" bottom="3" left="3" right="3"> <s:TextArea id="txtSrc" width="30%" height="100%"/> <s:TextArea id="txtOpreate" width="70%" height="100%"/> </mx:HDividedBox> </s:Application> |