无法使用XDocument从XML提取子元素 [英] Unable to extract child element from an XML using XDocument

问题描述

以下是我尝试从中提取子元素的XML。

Following is the XML from which I am trying to extract a child element.

<?xml version="1.0" encoding="UTF8"?>
<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<soap:Header xmlns="http://SomeValue/SomeValue/2009/01/SomeValue.xsd">
<Session>
<SessionId>SomeValue</SessionId>
<SequenceNumber>1</SequenceNumber>
<SecurityToken>SomeValue</SecurityToken>
</Session>
</soap:Header>
<soap:Body>
<Security_AuthenticateReply xmlns="http://SomeValue/SomeValue">
<processStatus>
<statusCode>P</statusCode>
</processStatus>
</Security_AuthenticateReply>
</soap:Body>
</soap:Envelope>

public static string AssignSecurityToken(string response)
{
        string Token = "";

        XNamespace ns = "http://schemas.xmlsoap.org/soap/envelope/";
        XElement xdoc = XElement.Parse(response);
        XElement root = xdoc.Descendants(ns + "Header").First();

        Token = root.Element("Session").Element("SecurityToken").Value;

        Token = root.Descendants("Session").Descendants().Where(n => n.Name == "SecurityToken").FirstOrDefault().Value;
        return Token;
}

我要提取元素安全令牌。

I want to extract the element Security Token.

以下是我已经做过的事情：

Following are the things that I have already worked on:

• 尝试使用
  >如何获取价值的方法中建议的方法XDocument的子节点

还发布了一些代码以供参考。
为Token变量赋值的两个语句都抛出对象未将
设置为对象的实例的异常。

Also posting some code for reference. Both the statements that are assigning values to the Token variable are throwing "Object not set to an instance of an object"exception.

预先感谢。

推荐答案

您需要考虑 Header 的命名空间。

You need to take into account the Header's namepace.

public static string AssignSecurityToken(string response)
{
    XNamespace ns1 = "http://schemas.xmlsoap.org/soap/envelope/";
    XNamespace ns2 = "http://SomeValue/SomeValue/2009/01/SomeValue.xsd";

    var envelope = XElement.Parse(response);
    var header = envelope.Element(ns1 + "Header");
    var session = header.Element(ns2 + "Session");
    var security_token = session.Element(ns2 + "SecurityToken");

    return security_token.Value;
}

实际上您可以继续拨打电话

Actually you could go ahead and just call

return XElement.Parse(response).Descendants()
            .First(x => x.Name.LocalName == "SecurityToken").Value;

这篇关于无法使用XDocument从XML提取子元素的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！