C# XElement 没有多次为同一个标签获取多个值
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【中文标题】C# XElement 没有多次为同一个标签获取多个值【英文标题】：C# XElement is not getting multiple Values for the same Tag multiple times 【发布时间】：2020-01-13 15:31:51 【问题描述】：我有这个 .graphml ：
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<graphml xmlns="http://graphml.graphdrawing.org/xmlns" xmlns:java="http://www.yworks.com/xml/yfiles-common/1.0/java" xmlns:sys="http://www.yworks.com/xml/yfiles-common/markup/primitives/2.0" xmlns:x="http://www.yworks.com/xml/yfiles-common/markup/2.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:y="http://www.yworks.com/xml/graphml" xmlns:yed="http://www.yworks.com/xml/yed/3" xsi:schemaLocation="http://graphml.graphdrawing.org/xmlns http://www.yworks.com/xml/schema/graphml/1.1/ygraphml.xsd">
<!--Created by yEd 3.19.1-->
<key for="port" id="d0" yfiles.type="portgraphics"/>
<key for="port" id="d1" yfiles.type="portgeometry"/>
<key for="port" id="d2" yfiles.type="portuserdata"/>
<key attr.name="url" attr.type="string" for="node" id="d3"/>
<key attr.name="description" attr.type="string" for="node" id="d4"/>
<key for="node" id="d5" yfiles.type="nodegraphics"/>
<key for="graphml" id="d6" yfiles.type="resources"/>
<key attr.name="url" attr.type="string" for="edge" id="d7"/>
<key attr.name="description" attr.type="string" for="edge" id="d8"/>
<key for="edge" id="d9" yfiles.type="edgegraphics"/>
<graph edgedefault="directed" id="G">
<node id="n0">
<data key="d5">
<y:UMLClassNode>
<y:Geometry x="1301.3333333333333" y="41.0"/>
<y:Fill color="#FFCC00" transparent="false"/>
<y:BorderStyle color="#000000" type="line" />
<y:NodeLabel alignment="center" autoSizePolicy="content" fontFamily="Dialog" fontSize="12" fontStyle="bold" hasBackgroundColor="false" hasLineColor="false" horizontalTextPosition="center" iconTextGap="4" modelName="internal" modelPosition="c" textColor="#000000" verticalTextPosition="bottom" visible="true" x="-3.87109375" xml:space="preserve" y="3.0"><<interface>>Employee</y:NodeLabel>
<y:UML clipContent="true" constraint="" hasDetailsColor="false" omitDetails="false" stereotype="" use3DEffect="true">
<y:AttributeLabel xml:space="preserve">+name:string
+age:int</y:AttributeLabel>
<y:MethodLabel xml:space="preserve">getName(value:string):String
getTitle():String
getStaffNo():Number
getRoom():String
getPhone()</y:MethodLabel>
</y:UML>
</y:UMLClassNode>
</data>
</node>
<node id="n1">
<data key="d3" xml:space="preserve"/>
<data key="d4"/>
<data key="d5">
<y:UMLClassNode>
<y:Geometry x="1422.0" y="197.0"/>
<y:Fill color="#FFCC00" transparent="false"/>
<y:BorderStyle color="#000000" type="line" />
<y:NodeLabel alignment="center" autoSizePolicy="content" fontFamily="Dialog" fontSize="13" fontStyle="bold" hasBackgroundColor="false" hasLineColor="false" horizontalTextPosition="center" iconTextGap="4" modelName="custom" textColor="#000000" verticalTextPosition="bottom" visible="true" x="70.661376953125" xml:space="preserve" y="3.0">Customer<y:LabelModel><y:SmartNodeLabelModel distance="4.0"/></y:LabelModel><y:ModelParameter><y:SmartNodeLabelModelParameter labelRatioX="0.0" labelRatioY="0.0" nodeRatioX="0.0" nodeRatioY="0.0" offsetX="0.0" offsetY="0.0" upX="0.0" upY="-1.0"/></y:ModelParameter></y:NodeLabel>
<y:UML clipContent="true" constraint="" hasDetailsColor="false" omitDetails="false" stereotype="" use3DEffect="true">
<y:AttributeLabel xml:space="preserve">+name:string</y:AttributeLabel>
<y:MethodLabel xml:space="preserve">+getOrder():string
+payOrder(order:string):int</y:MethodLabel>
</y:UML>
</y:UMLClassNode>
</data>
</node>
<node id="n2">
<data key="d3" xml:space="preserve"/>
<data key="d4"/>
<data key="d5">
<y:UMLClassNode>
<y:Geometry x="1086.0" y="197.0"/>
<y:Fill color="#FFCC00" transparent="false"/>
<y:BorderStyle color="#000000" type="line" />
<y:NodeLabel alignment="center" autoSizePolicy="content" fontFamily="Dialog" fontSize="13" fontStyle="bold" hasBackgroundColor="false" hasLineColor="false" horizontalTextPosition="center" iconTextGap="4" modelName="custom" textColor="#000000" verticalTextPosition="bottom" visible="true" x="33.54638671875" xml:space="preserve" y="3.0">User<y:LabelModel><y:SmartNodeLabelModel distance="4.0"/></y:LabelModel><y:ModelParameter><y:SmartNodeLabelModelParameter labelRatioX="0.0" labelRatioY="0.0" nodeRatioX="0.0" nodeRatioY="0.0" offsetX="0.0" offsetY="0.0" upX="0.0" upY="-1.0"/></y:ModelParameter></y:NodeLabel>
<y:UML clipContent="true" constraint="" hasDetailsColor="false" omitDetails="false" stereotype="" use3DEffect="true">
<y:AttributeLabel xml:space="preserve">+name:string</y:AttributeLabel>
<y:MethodLabel xml:space="preserve">getName()</y:MethodLabel>
</y:UML>
</y:UMLClassNode>
</data>
</node>
</graph>
<data key="d6">
<y:Resources/>
</data>
</graphml>
这段代码：
public List<Key> AnalyzeNode(XmlReader reader, string filepath)
XDocument doc = XDocument.Load(filepath);
XNamespace ns = doc.Root.GetDefaultNamespace();
List<Key> keys = doc.Descendants(ns + "node").Select(x => new Key()
id = (string)x.Attribute("id"),
baseModel = AnalyzeNodeLabel<UML_Base>(reader, (string)x.Attribute("id"))
).ToList();
return keys;
public T AnalyzeNodeLabel<T>(XmlReader reader, string id) where T : UML_Base
while (reader.Read())
XDocument doc = XDocument.Load(this.filepath);
XNamespace ns = "http://www.yworks.com/xml/graphml";
XElement element = doc.Descendants(ns + "NodeLabel").FirstOrDefault();
string interfaceName = element.Value;
if (interfaceName.Contains("<<interface>>") || interfaceName.Contains("interface") || interfaceName.StartsWith("I") && interfaceName.Substring(0, 1).ToUpper().Equals(interfaceName))
UML_Interface interfaceModel = new UML_Interface(interfaceName, id);
return (T)Convert.ChangeType(interfaceModel, typeof(UML_Interface));
if (interfaceName != null && !interfaceName.Contains("<<interface>>") || !interfaceName.Contains("interface") || !interfaceName.StartsWith("I") && !interfaceName.Substring(0, 1).ToUpper().Equals(interfaceName))
UML_Class classModel = new UML_Class(interfaceName, id);
return (T)Convert.ChangeType(classModel, typeof(UML_Class));
return null;
我的问题是 XElement 只获得一个值，但有 3 个 <y:NodeLabel>Tags 具有不同的值。价值观是指文本。但是我的 XElement 对象 (from AnalyzeNodeLabel()) 只是从第一个 <y:NodeLabel> 标记中获取值，我怎样才能添加其他的呢？也许作为列表？或在一个循环后更新值？那可能吗？
【问题讨论】：
使用：List您明确选择第一次出现的节点：FirstOrDefault() 您必须在循环中选择节点：
foreach (var element in doc.Descendants(ns + "NodeLabel"))
...
更新： 我不知道您为什么打开 Xml 文件两次或 XmlReader 发生了什么。 如果您只对节点“node”和“NodeLabel”（可能不止一个）感兴趣，那么这可能会有所帮助：
XNamespace yns = "http://www.yworks.com/xml/graphml";
Dictionary<string, List<string>> keys = new Dictionary<string, List<string>>();
foreach (var node in doc.Descendants(ns + "node"))
keys[node.Attribute("id").Value] = new List<string>();
foreach (var nodeLabel in node.Descendants(yns + "NodeLabel"))
keys[node.Attribute("id").Value].Add(nodeLabel.Value);
foreach (var entry in keys)
Console.WriteLine($"Key: entry.Key");
foreach (var basemodel in entry.Value)
Console.WriteLine($"->basemodel: basemodel");
输出是： 键：n0 ->基础模型：>员工 键：n1 ->基础模型：客户 键：n2 ->基本模型：用户
【讨论】：
是的，你是对的，但是当我这样做时，我得到了所有不同的 element.Values 但 id 总是相同的，因为使用x.Attribute("id") 一个对象的值调用该方法创建的。我也需要其他身份证
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