flex xml Children() 方法奇怪的行为

Question

我有以下 xml 声明：

public var reqData:XML = <root>
  <Requirement ID="REQ-GEN-0.1" title="exigence gen 1" description="blabla 01" testable="true"/>
  <RequirementSet ID="GUI REQ">
    <Requirement ID="REQ-GUI-1.1" title="exigence ihm 1" description="blabla 11" testable="true"/>
    <Requirement ID="REQ-GUI-1.2" title="exigence ihm 2" description="blabla 12" testable="false"/>
  </RequirementSet>
  <RequirementSet ID="PERF REQ">
    <Requirement ID="REQ-PERF-2.1" title="exigence perf 1" description="blabla 21" testable="true"/>
    <Requirement ID="REQ-PERF-2.2" title="exigence perf 2" description="blabla 22" testable="false"/>
    <Requirement ID="REQ-PERF-2.3" title="exigence perf 3" description="blabla 23" testable="true"/>
    <Requirement ID="REQ-PERF-2.4" title="exigence perf 4" description="blabla 24" testable="false"/>
    <Requirement ID="REQ-PERF-2.5" title="exigence perf 5" description="blabla 25" testable="false"/>
    <Requirement ID="REQ-PERF-2.6" title="exigence perf 6" description="blabla 26" testable="false"/>
  </RequirementSet>
  <RequirementSet ID="BUS REQ">
    <RequirementSet ID="BUS 1 REQ">
      <Requirement ID="REQ-BUS-3.1.1" title="exigence bus 1" description="blabla 311" testable="false"/>
      <Requirement ID="REQ-BUS-3.1.2" title="exigence bus 2" description="blabla 312" testable="true"/>
    </RequirementSet>
    <RequirementSet ID="BUS 2 REQ">
      <Requirement ID="REQ-BUS-3.2.1" title="exigence bus3" description="blabla 321" testable="true"/>
    </RequirementSet>
    <RequirementSet ID="BUS 3 REQ"/>
  </RequirementSet>
</root>;

我用此 xml 填充了高级数据网格，但问题是未检测到要求：

我已经重写了 HierarchicalData 类的方法来查看发生了什么：

override public function canHaveChildren(node:Object):Boolean
        {
            if (node is XML && node != null){
                var xmlNode:XML = node as XML;
                trace("node:"+node);
                trace("node.children:"+node.children());
                trace("xmlNode.name:"+xmlNode.name());
                trace("xmlNode.localName:"+xmlNode.localName());
                trace("xmlNode.attributes:"+xmlNode.attributes());
                trace("xmlNode.attributes:"+xmlNode.nodeKind());
                trace("xmlNode.children():"+xmlNode.children());
                trace("xmlNode.children().length():"+xmlNode.children().length());

                if(xmlNode.children().length()>0){
                    var xmlNodeChildren:XMLList = xmlNode.children() as XMLList;
                    var xmlNodeFirstChild:XML = xmlNodeChildren[0];
                    trace("xmlNodeFirstChild:"+xmlNodeFirstChild);
                    trace("xmlNodeFirstChild.name():"+xmlNodeFirstChild.name());
                    trace("xmlNodeFirstChild.comments():"+xmlNodeFirstChild.comments());
                    trace("xmlNodeFirstChild.attributes():"+xmlNodeFirstChild.attributes());
                    trace("xmlNodeFirstChild.nodeKind():"+xmlNodeFirstChild.nodeKind());
                    trace("xmlNodeFirstChild.descendants():"+xmlNodeFirstChild.descendants());
                }


            } 

这是结果（控制台），我只是根本不明白：

node:<RequirementSet ID="BUS 2 REQ">
  <Requirement ID="REQ-BUS-3.2.1" title="exigence bus3" description="blabla 321" testable="true"/>
</RequirementSet>
node.children:
xmlNode.name:RequirementSet
xmlNode.localName:RequirementSet
xmlNode.attributes:BUS 2 REQ
xmlNode.attributes:element
xmlNode.children():
xmlNode.children().length():1
xmlNodeFirstChild:
xmlNodeFirstChild.name():Requirement
xmlNodeFirstChild.comments():
xmlNodeFirstChild.attributes():REQ-BUS-3.2.1exigence bus3blabla 321true
xmlNodeFirstChild.nodeKind():element
xmlNodeFirstChild.descendants():

children() 方法未检测到该节点，但它存在。问题是我无法查看 XML.abc 的源代码，因为它不是开源的。有人能告诉我发生了什么事吗？这是一个错误还是其他什么？

Answer 1

该节点由 children() 方法按照您的预期方式选取，因为否则 children() 的 length() 将是0.你要明白的是，trace(node.children());实际上意味着trace(XMLList(node.children()).toString()); - 您正在 XMLList 上调用 toString() - 其输出可能有许多不同的结果，但显然不是非常可预测的结果：

var xml : XML = <node><child>MyText</child></node>;
trace ( xml.children () ); 
// => MyText

xml = <node><child value="MyText" /></node>;
trace ( xml.children () ); 
// => nothing

xml = <node><child key="myKey" id="1" value="MyText" /></node>;
trace ( xml.children () ); 
// => nothing

xml = <node><child id="1" key="text">MyText</child></node>;
trace ( xml.children () ); 
// => MyText

xml = <node><child id="1">MyText<child id="2">MyOtherText</child></child></node>;
trace ( xml.children () ); 
// => <child id="1">MyText<child id="2">MyOtherText</child></child>

为了确保获得子节点的完整 xml，请尝试：

var childXML : String = node.children().length() > 0 ? node.children()[0].toXMLString():"empty");
trace("node.child#0:"+ childXML);
// output: 
// node.child#0:<Requirement ID="REQ-BUS-3.2.1" title="exigence bus3" description="blabla 321" testable="true"/>