Question

我正在尝试读取Xml数据并将其加载到String of List中。但是我无法完成它。以下是我的代码。

昏暗的结果As String =“”

    Dim soap As String = "<?xml version=""1.0"" encoding=""utf-8""?>" & vbCr & vbLf & "<soap:Envelope xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"" " & vbCr & vbLf & "   xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" " & vbCr & vbLf & "   xmlns:soap=""http://schemas.xmlsoap.org/soap/envelope/"">" & vbCr & vbLf & "  <soap:Body>" & vbCr & vbLf & "    <Register xmlns=""http://tempuri.org/"">" & vbCr & vbLf & "      <id>123</id>" & vbCr & vbLf & "      <data1>string</data1>" & vbCr & vbLf & "    </Register>" & vbCr & vbLf & "  </soap:Body>" & vbCr & vbLf & "</soap:Envelope>"

    Dim req As HttpWebRequest = DirectCast(WebRequest.Create("http://localhost:59924/WebService.asmx/HelloWorld"), HttpWebRequest)
    req.Headers.Add("SOAPAction", """http://tempuri.org/Register""")
    req.ContentType = "text/xml;charset=""utf-16"""
    req.Accept = "text/xml"
    req.Method = "POST"
    'req.ContentLength = strCritera.Length
    req.UserAgent = "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.1) Gecko/2008070208 Firefox/3.0.1"
    req.Accept = "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8"

    Dim requestWriter As New StreamWriter(req.GetRequestStream())
    requestWriter.Close()

    Dim responseReader As New StreamReader(req.GetResponse().GetResponseStream())
    Dim responseData As String = responseReader.ReadToEnd()

    Dim fileName As String = responseData

    Dim doc As New XmlDocument()

    doc.LoadXml(fileName)

    Dim categories As New List(Of String)()

    Dim nList As XmlNodeList = doc.SelectNodes("/ArrayOfString/string")

    For Each node As XmlNode In nList
        categories.Add(node.ToString())
    Next

我得到的nList为0计数。下面是我从Web服务获取的xml数据。

<?xml version="1.0" encoding="utf-8"?>
<ArrayOfString xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://tempuri.org/">
  <string>Test1</string>
  <string>Test2</string>
  <string>Test3</string>
  <string>Test4</string>
  <string>Test5</string>
  <string>Test7</string>
</ArrayOfString>

Answer 1

这是因为xml具有默认命名空间（xmlns="http://tempuri.org/"），因此您需要在XPath查询中使用前缀并使用XmlNamespaceManager来定义前缀：

.....
Dim namespaceManager As XmlNamespaceManager = New XmlNamespaceManager(doc.NameTable)
namespaceManager.AddNamespace("d", "http://tempuri.org/")
Dim nList As XmlNodeList = doc.SelectNodes("/d:ArrayOfString/d:string", namespaceManager)
......

在XPath查询中未提供前缀时，它将被视为没有命名空间的元素。在XML中，当文件声明了默认名称空间时，所有没有前缀的元素都将被视为默认名称空间[Reference]。

读取Xml Array of String并将其加载到List（Of String）中

1 个答案: