Question

这是我第一次使用XPath。

这是我的XML：

<content type="application/xml">
    <m:properties xmlns:m="http://schemas.microsoft.com/ado/2007/08/dataservices/metadata" xmlns:d="http://schemas.microsoft.com/ado/2007/08/dataservices">
        <d:Guid>YOIYOI-HNON-OIN</d:Guid>
        <d:ObjectId>6000009251</d:ObjectId>
        <d:ProcessType>ZMIN</d:ProcessType>
        <d:ProcessTypeTxt>Incident</d:ProcessTypeTxt>
        <d:Description>Test 2</d:Description>
        <d:IntroText>Incident</d:IntroText>
        <d:CreatedAtDateFormatted>08.05.18</d:CreatedAtDateFormatted>
        <d:ChangedAtDateFormatted>08.05.18</d:ChangedAtDateFormatted>
        <d:PostingDate>2018-05-08T00:00:00</d:PostingDate>
        <d:ChangedAtDate>2018-05-08T00:00:00</d:ChangedAtDate>
        <d:Priority>2</d:Priority>
        <d:PriorityTxt>2: High</d:PriorityTxt>
        <d:PriorityState>None</d:PriorityState>
        <d:Concatstatuser>New</d:Concatstatuser>
        <d:ActionRequired>false</d:ActionRequired>
        <d:StillOpen>true</d:StillOpen>
        <d:Icon></d:Icon>
        <d:SoldToPartyName></d:SoldToPartyName>
        <d:ServiceTeamName></d:ServiceTeamName>
        <d:PersonRespName></d:PersonRespName>
        <d:ConfigItemTxt></d:ConfigItemTxt>
    </m:properties>
</content>

还有其他内容节点。

我需要检索特定的标签值，例如：

d：Guid
d：ProcessType
d：说明
依此类推。

但是我不需要所有标签值。

我尝试了一个在线Xpath验证器，在其中发布了XML并使用了以下表达式：

//content/m:properties/d:Guid | //content/m:properties/d:ObjectId

这给了我所需的数据，但是当我在c＃应用程序中使用它时，它返回null。有人可以向我解释为什么会这样吗？还有，除了使用XPath之外，还有其他方法吗？

这是我的C＃代码：

string xml = System.IO.File.ReadAllText(startupPath);
StringBuilder sb = new StringBuilder();

using (var node = ChoXmlReader.LoadText(xml).WithXPath("//content/m:properties/d:Guid or //content/m:properties/d:ObjectId"))
{
    using (var w = new ChoCSVWriter(sb).WithFirstLineHeader())
    {
        w.Write(node);
    }
}

Console.WriteLine(sb.ToString());
Console.ReadLine();

Answer 1

在在线验证器中，您使用|，但在代码中使用or。 ChoETL是否真的改变了XPaths的工作方式？我在文档中找不到证据。

此外，我认为在线工具会自动推断出名称空间前缀，但是您需要告诉ChoETL名称空间：

.WithXNamespace("d", "http://schemas.microsoft.com/ado/2007/08/dataservices")

和类似的

Answer 2

您可以为此XML文件创建模型，然后将其序列化为对象，然后访问所需的属性。这是您可以使用的模型：

[XmlRoot(ElementName = "properties", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata")]
    public class Properties
    {
        [XmlElement(ElementName = "Guid", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string Guid { get; set; }
        [XmlElement(ElementName = "ObjectId", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ObjectId { get; set; }
        [XmlElement(ElementName = "ProcessType", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ProcessType { get; set; }
        [XmlElement(ElementName = "ProcessTypeTxt", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ProcessTypeTxt { get; set; }
        [XmlElement(ElementName = "Description", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string Description { get; set; }
        [XmlElement(ElementName = "IntroText", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string IntroText { get; set; }
        [XmlElement(ElementName = "CreatedAtDateFormatted", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string CreatedAtDateFormatted { get; set; }
        [XmlElement(ElementName = "ChangedAtDateFormatted", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ChangedAtDateFormatted { get; set; }
        [XmlElement(ElementName = "PostingDate", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string PostingDate { get; set; }
        [XmlElement(ElementName = "ChangedAtDate", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ChangedAtDate { get; set; }
        [XmlElement(ElementName = "Priority", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string Priority { get; set; }
        [XmlElement(ElementName = "PriorityTxt", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string PriorityTxt { get; set; }
        [XmlElement(ElementName = "PriorityState", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string PriorityState { get; set; }
        [XmlElement(ElementName = "Concatstatuser", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string Concatstatuser { get; set; }
        [XmlElement(ElementName = "ActionRequired", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ActionRequired { get; set; }
        [XmlElement(ElementName = "StillOpen", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string StillOpen { get; set; }
        [XmlElement(ElementName = "Icon", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string Icon { get; set; }
        [XmlElement(ElementName = "SoldToPartyName", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string SoldToPartyName { get; set; }
        [XmlElement(ElementName = "ServiceTeamName", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ServiceTeamName { get; set; }
        [XmlElement(ElementName = "PersonRespName", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string PersonRespName { get; set; }
        [XmlElement(ElementName = "ConfigItemTxt", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices")]
        public string ConfigItemTxt { get; set; }
        [XmlAttribute(AttributeName = "m", Namespace = "http://www.w3.org/2000/xmlns/")]
        public string M { get; set; }
        [XmlAttribute(AttributeName = "d", Namespace = "http://www.w3.org/2000/xmlns/")]
        public string D { get; set; }
    }

    [XmlRoot(ElementName = "content")]
    public class Content
    {
        [XmlElement(ElementName = "properties", Namespace = "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata")]
        public Properties Properties { get; set; }
        [XmlAttribute(AttributeName = "type")]
        public string Type { get; set; }
    }

这是C#代码，可将其转换为对象：

XmlSerializer serializer = new XmlSerializer(typeof(Content));
 Content resultingMessage = (Content)serializer.Deserialize(new XmlTextReader(@"XMLFile1.xml"));

这是访问guid属性的代码：

string guid = resultingMessage.Properties.Guid;

希望这可以解决您的问题。

PS：我已经基于给定的XML文件创建了模型，如果对此XML schema进行了更改，则需要相应地修改model。

快乐的编码...

Answer 3

以下是使用Cinchoo ETL将选择性xml节点输出到csv文件的方法

var nsManager = new XmlNamespaceManager(new NameTable());
//register mapping of prefix to namespace uri 
nsManager.AddNamespace("m", "http://schemas.microsoft.com/ado/2007/08/dataservices/metadata");
nsManager.AddNamespace("d", "http://schemas.microsoft.com/ado/2007/08/dataservices");

StringBuilder csv = new StringBuilder();
using (var p = ChoXmlReader.LoadText(xml)
        .WithXPath("//entry/content/m:properties")
        .WithXmlNamespaceManager(nsManager)
        .WithField("Guid", xPath: "d:Guid")
        .WithField("ProcessType", xPath: "d:ProcessType")
        .WithField("Description", xPath: "d:Description")
    )
{
    using (var w = new ChoCSVWriter(csv)
        .WithFirstLineHeader()
        )
        w.Write(p);
}

Console.WriteLine(csv);

XPath在c＃中返回null，但在XPath验证程序中有效

3 个答案: