我有一个如下所示的 XElement:
<User ID="11" Name="Juan Diaz" LoginName="DN1\jdiaz" xmlns="http://schemas.microsoft.com/sharepoint/soap/directory/" />
如何使用 XML 提取 LoginName 属性的值?我尝试了以下操作,但 q2“枚举没有结果”。
var q2 = from node in el.Descendants("User")
let loginName = node.Attribute(ns + "LoginName")
select new { LoginName = (loginName != null) };
foreach (var node in q2)
{
Console.WriteLine("LoginName={0}", node.LoginName);
}
var xml = @"<User ID=""11""
Name=""Juan Diaz""
LoginName=""DN1\jdiaz""
xmlns=""http://schemas.microsoft.com/sharepoint/soap/directory/"" />";
var user = XElement.Parse(xml);
var login = user.Attribute("LoginName").Value; // "DN1\jdiaz"
XmlDocument doc = new XmlDocument();
doc.Load("myFile.xml"); //load your xml file
XmlNode user = doc.getElementByTagName("User"); //find node by tag name
string login = user.Attributes["LoginName"] != null ? user.Attributes["LoginName"].Value : "unknown login";
最后一行代码,设置
string login
,格式如下...
var variable = condition ? A : B;
基本上是说,如果条件为
true
,则变量等于 A,否则变量等于 B。
来自 XAttribute.Value 的文档:
如果您获取值并且该属性可能不存在,则使用显式转换运算符并将属性分配给可空类型(例如
或string
的Nullable<T>
)会更方便。如果该属性不存在,则可空类型设置为 null。Int32
如果这是 VB .Net 那么这可能是一个更好的方法。
Function ExtractDataFromXML2(ByRef sInputXML As String) As String
Dim anElement As XElement
Dim sError As String
Dim sMessageID As String
Dim sResult As String = ""
Try
anElement = XElement.Parse(sInputXML)
Dim Node As XElement = anElement.<push-response>.FirstOrDefault
sError = Node.<response-result>.@code
sMessageID = Node.Attribute("push-id").Value
If sError = "1000" Then
sResult = Node.<address>.Value & "@" & sMessageID
Else
sResult = "Error " & sError & ": " & Node.<response-result>.@desc
End If
Catch ex As Exception
sResult = "XML Parse Error: " & ex.Message & " code=" & ex.Source & " " & ControlChars.CrLf
End Try
Return sResult
End Function
我最终使用字符串操作来获取值,因此我将发布该代码,但我仍然希望看到一种 XML 方法(如果有的话)。
string strEl = el.ToString();
string[] words = strEl.Split(' ');
foreach (string word in words)
{
if (word.StartsWith("LoginName"))
{
strEl = word;
int first = strEl.IndexOf("\"");
int last = strEl.LastIndexOf("\"");
string str2 = strEl.Substring(first + 1, last - first - 1);
//str2 = "dn1\jdiaz"
}
}