解析 xml 字符串并消除根元素错误

Question

我将此字符串结构化为 XML:

<damp fullmedia="">
  <mediaitem>
    <img id="1119" version="29a5623f-d41c-4418-97b7-3cea8579ffd8" parentid="1052" level="2" writerid="0" nodetype="1032" template="0" sortorder="2" createdate="2016-11-30T10:09:40" updatedate="2016-11-30T10:09:40" nodename="2016-11-25_1251411957-277" urlname="2016-11-25_1251411957-277" writername="admin" nodetypealias="Image" path="-1,1052,1119">
      <umbracofile>/media/1013/2016-11-25_1251411957-277.jpg</umbracofile>
      <umbracowidth>2598</umbracowidth>
      <umbracoheight>1732</umbracoheight>
      <umbracobytes>350613</umbracobytes>
      <umbracoextension>jpg</umbracoextension>    
    </img>
  </mediaitem>
</damp>

我想提取属性"umbracofile"的值，所以我这样做了：

var stringAsXml = "<damp fullmedia="">....";
var xmlDoc = new XmlDocument();
var imageUrl = xmlDoc.SelectSingleNode("//mediaItem/img/umbracoFile").InnerText;

代码工作正常，但出现错误 "Root element is missing"。由于我只想解析和提取节点值，我该如何摆脱这个错误？

Answer 1

The code works fine but I have the error "Root element is missing".

那么我猜代码不能正常工作？这应该有效：

var stringAsXml = "<damp fullmedia=\"\"><mediaitem><img id=\"1119\" version=\"29a5623f-d41c-4418-97b7-3cea8579ffd8\" parentid=\"1052\" level=\"2\" writerid=\"0\" nodetype=\"1032\" template=\"0\" sortorder=\"2\" createdate=\"2016-11-30T10:09:40\" updatedate=\"2016-11-30T10:09:40\" nodename=\"2016-11-25_1251411957-277\" urlname=\"2016-11-25_1251411957-277\" writername=\"admin\" nodetypealias=\"Image\" path=\"-1,1052,1119\"><umbracofile>/media/1013/2016-11-25_1251411957-277.jpg</umbracofile><umbracowidth>2598</umbracowidth><umbracoheight>1732</umbracoheight><umbracobytes>350613</umbracobytes><umbracoextension>jpg</umbracoextension></img></mediaitem></damp>";
var xmlDoc = new XmlDocument();
xmlDoc.LoadXml(stringAsXml);
var imageUrl = xmlDoc.SelectSingleNode("damp/mediaitem/img/umbracofile").InnerText;

还有这个（如果你有几个 <umbracofile> 节点并且想要 select 第一个）：

var imageUrl = xmlDoc.SelectSingleNode("//umbracofile").InnerText;

解析 xml 字符串并消除根元素错误

Parsing xml string and get rid of root element error

c#

xml

umbraco

xml-parsing