How can I use DataContractSerializer to deserialize from a single node of an XMLDocument?
The开发者_如何学JAVA readers that DataContractSerializer uses in ReadObject seem to be stream-based. I already have an XMLDocument, and I would like to deserialize one part of that document.
In this code snippet, I am deserializing a MyItem object from a filestream:
Dim fs As New FileStream("c:\myinputfile.xml", FileMode.Open)
Dim reader As XmlDictionaryReader = XmlDictionaryReader.CreateTextReader(fs, New XmlDictionaryReaderQuotas())
Dim ser As New DataContractSerializer(GetType(MyItemClass))
Dim deserializedMyItem As ClassTemplate = CType(ser.ReadObject(reader, True), MyItemClass)
but what if instead I want to deserialize just a part of a document.
Dim MyItemNode as Xml.XmlNode = parentDoc.selectSingleNode("MyItemElementName")
Dim deserializedMyItem As MyItemClass = getMyItemFromNode(MyItemNode)
What does getMyItemFromNode look like?
Unless there is a better way that streaming it, here's a solution using the memorystream:
Function getMyItemFromNode(ByVal itemNode as Xml.XmlNode) as MyItemClass
Dim stm As New MemoryStream()
Dim stw As New StreamWriter(stm)
stw.Write(itemNode.OuterXml)
stw.Flush()
stm.Position = 0
Dim reader As XmlDictionaryReader = XmlDictionaryReader.CreateTextReader(stm, New XmlDictionaryReaderQuotas())
Dim ser As New DataContractSerializer(GetType(MyItemClass))
Return CType(ser.ReadObject(reader, True), MyItemClass)
End Function
Code for pushing it to a stream came from this response to a related question.
Use [CreateDictionaryReader](http://msdn.microsoft.com/en-us/library/system.xml.xmldictionaryreader.createdictionaryreader.aspx) with an
XmlReader` pointing to the node you want:
Dim doc As XmlDocument = new XmlDocument()
' fill it
Dim nav as XPathNavigator = doc.CreateNavigator()
Dim docReader As XmlReader = nav.ReadSubTree()
Dim reader As XmlDictionaryReader = _
XmlDictionaryReader.CreateDictionaryReader(docReader)
Dim ser As New DataContractSerializer(GetType(MyItemClass))
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