使用XmlDocument.SelectNodes遍历xml元素遇到的一个XPathException

时间:2023-03-08 18:10:12

使用XmlDocument类时候报错:

未处理的XPathException:
需要命名空间管理器或 XsltContext。此查询具有前缀、变量或用户定义的函数。

需要使用XmlNamespaceManager类:Resolves, adds, and removes namespaces to a collection and provides scope management for these namespaces.

这是因为使用的soap文档含有自己的命名空间。相同问题:http://bbs.csdn.net/topics/350101606

最终修改后的代码:

 string soap = "";
soap += "<SOAP-ENV:Envelope xmlns:SOAP-ENV=\"http://schemas.xmlsoap.org/soap/envelope/\">";
soap += "<SOAP-ENV:Body>";
soap += "<AP-MSG:SubscriptionRequest xmlns:AP-MSG=\"http://www.vestas.dk/2001/04/ap\" xmlns:SOAP-ENC=\"http://schemas.xmlsoap.org/soap/encoding/\">";
soap += "<RequestBase ClientRequestHandle=\"41\" ReturnItemTime=\"false\" ReturnItemName=\"true\" CallbackURL=\"10.116.21.222:1055\" CallbackRate=\"PT10S\"/>";
soap += "<ItemRequestSpec MaxAge=\"PT0.1S\"/>";
soap += "<ItemList>";
foreach (IoTag tag in Tags)
{
soap += string.Format("<Item ItemName=\"{0}\"/>", tag.Name);
}
soap += "</ItemList>";
soap += "</AP-MSG:SubscriptionRequest>";
soap += "</SOAP-ENV:Body>";
soap += "</SOAP-ENV:Envelope>";
string subscriptionRequest = "";
subscriptionRequest += "POST * HTTP/1.1\r\n";
subscriptionRequest += "Content-Type:text/xml;charset=ISO-8859-1\r\n";
subscriptionRequest += "Connection:Keep-Alive\r\n";
subscriptionRequest += "SOAPAction:http://www.vestas.dk/2001/04/ap#SubscriptionRequest\r\n";
subscriptionRequest += string.Format("Content-Length:{0}\r\n", soap.Length);
subscriptionRequest += "\r\n";
subscriptionRequest += soap; XmlDocument xDoc = new XmlDocument();
xDoc.LoadXml(soap);
XmlNamespaceManager nsMgr = new XmlNamespaceManager(xDoc.NameTable);
nsMgr.AddNamespace("SOAP-ENV", "http://schemas.xmlsoap.org/soap/envelope/");
nsMgr.AddNamespace("AP-MSG", "http://www.vestas.dk/2001/04/ap");
nsMgr.AddNamespace("SOAP-ENC", "http://schemas.xmlsoap.org/soap/encoding/"
);
XmlElement xe = xDoc.DocumentElement;
XmlNodeList xnl = xDoc.SelectNodes("/SOAP-ENV:Envelope/SOAP-ENV:Body/AP-MSG:SubscriptionRequest/ItemList/Item", nsMgr);             foreach (XmlNode item in xnl)
{
string s = item.Attributes["ItemName"].Value;
}