Flex之旅：第一部分：flex必备基础知识积累(6)---XML, XMLList, XMLListCollection的区别（二）

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茜茜770 2022-12-06 10:37:08 博主文章分类：flex ©著作权

文章标签 xml tomcat java 文章分类 运维

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XMLList

XMLList的特点就是没有根节点。

1直接赋值XMLList的写法

<?xml version="1.0" encoding="utf-8"?>
<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"
         minWidth="955" minHeight="600"
         creationComplete="application1_creationCompleteHandler(event)">
  <fx:Script>
    <![CDATA[
      import mx.events.FlexEvent;
      protected function application1_creationCompleteHandler(event:FlexEvent):void
      {
        // 1直接赋值
        var xmlList1:XMLList = 
          <>
            <node age="18" label="tomcat" />
            <node age="20" label="java" />
            <node age="30" label="webLogic" />
          </>;
        trace(xmlList1);  
        
        
      }
      
    ]]>
  </fx:Script>
</s:Application>

注意：

XMLList虽然是没有根节点，
但是如果在直接赋值的时候，还是需要一对空标签( <> </> )，将内容包起来！！！！
赋值的时候，一对空标签是不会赋值给XMLList的。
所以trace的时候，一对空标签一定不会打印出来的。

2通过XML取得XMLList的方法如下：

<?xml version="1.0" encoding="utf-8"?>
<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"
         minWidth="955" minHeight="600"
         creationComplete="application1_creationCompleteHandler(event)" xmlns:vo="vo.*">
  <fx:Script>
    <![CDATA[
      import mx.events.FlexEvent;
      protected function application1_creationCompleteHandler(event:FlexEvent):void
      {
        var xml:XML = 
          <root>
            <node age="18" label="tomcat" >
              <item version="5.0" />
              <item version="6.0" />
              <item version="7.0" />
            </node>
            <node age="20" label="java" >
              <item version="1.5" >
                <node version="xx" />
                <node version="yy" />
                <node version="zz" />
              </item>
              <item version="1.6" />
              <item version="1.7" />
            </node>
            <node age="30" label="webLogic" >
            </node>
          </root>;

        var xmlList2:XMLList = xml.elements("node");
        trace("---------------------");
        trace(xmlList2);
        
      }
      
    ]]>
  </fx:Script>
  
</s:Application>

注意，经过测试，XML.elements()方法可以返回仅仅是下一级别的XMLList

console:

3 通过XMLList取得XMLList的方法如下：

<?xml version="1.0" encoding="utf-8"?>
<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"
         minWidth="955" minHeight="600"
         creationComplete="application1_creationCompleteHandler(event)" xmlns:vo="vo.*">
  <fx:Script>
    <![CDATA[
      import mx.events.FlexEvent;
      protected function application1_creationCompleteHandler(event:FlexEvent):void
      {
        var xml:XML = 
          <root>
            <node age="18" label="tomcat" >
              <item version="5.0" />
              <item version="6.0" />
              <item version="7.0" />
            </node>
            <node age="20" label="java" >
              <item version="1.5" >
                <node version="xx" />
                <node version="yy" />
                <node version="zz" />
              </item>
              <item version="1.6" />
              <item version="1.7" />
            </node>
            <node age="30" label="webLogic" >
            </node>
          </root>;

        var xmlList2:XMLList = xml.elements("node");
        trace("---------------------");
        trace(xmlList2);
        
        var xmlList3:XMLList = xmlList2.elements("item");
        trace("---------------------");
        trace(xmlList3);
      }
      
    ]]>
  </fx:Script>
  
  
  
</s:Application>

console:

---------------------
<node age="18" label="tomcat">
<item version="5.0"/>
<item version="6.0"/>
<item version="7.0"/>
</node>
<node age="20" label="java">
<item version="1.5">
<node version="xx"/>
<node version="yy"/>
<node version="zz"/>
</item>
<item version="1.6"/>
<item version="1.7"/>
</node>
<node age="30" label="webLogic"/>
---------------------
<item version="5.0"/>
<item version="6.0"/>
<item version="7.0"/>
<item version="1.5">
<node version="xx"/>
<node version="yy"/>
<node version="zz"/>
</item>
<item version="1.6"/>
<item version="1.7"/>

注意，XMLList.elements()方法可以返回当前XMLList所有一级节点的下一级别的XMLList

4 标签定义写法：

<?xml version="1.0" encoding="utf-8"?>
<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"
         minWidth="955" minHeight="600"
         creationComplete="application1_creationCompleteHandler(event)">
  <fx:Script>
    <![CDATA[
      import mx.events.FlexEvent;
      protected function application1_creationCompleteHandler(event:FlexEvent):void
      {
        trace("---------------------");
        trace(xml1);
      }
      
    ]]>
  </fx:Script>
  
  <fx:Declarations>
    <fx:XMLList id="xml1">
        <node age="18" label="tomcat" >
          <item version="5.0" />
          <item version="6.0" />
          <item version="7.0" />
        </node>
        <node age="20" label="java" >
          <item version="1.5" >
            <node version="xx" />
            <node version="yy" />
            <node version="zz" />
          </item>
          <item version="1.6" />
          <item version="1.7" />
        </node>
        <node age="30" label="webLogic" >
        </node>
    </fx:XMLList>
  </fx:Declarations>
  
</s:Application>