DataContractSerializer.IsStartObject Method (XmlDictionaryReader)


The .NET API Reference documentation has a new home. Visit the .NET API Browser on to see the new experience.

Determines whether the XmlDictionaryReader is positioned on an object that can be deserialized.

Namespace:   System.Runtime.Serialization
Assembly:  System.Runtime.Serialization (in System.Runtime.Serialization.dll)

Public Overrides Function IsStartObject (
	reader As XmlDictionaryReader
) As Boolean


Type: System.Xml.XmlDictionaryReader

An XmlDictionaryReader used to read the XML stream.

Return Value

Type: System.Boolean

true if the reader is at the start element of the stream to read; otherwise, false.

The IsStartObject determines whether it can read an object by checking that it is positioned on an XML element. It also examines the name and namespace of the XML element that the reader is positioned at and compares the values to the expected name and namespace. The expected name and namespace can be set with the following: the data contract name and namespace of the type passed into the constructor, or the rootName and rootNamespace values passed into the constructor (if present).

The following example uses the IsStartObject property to determine whether the start of the data has been found.

Public Shared Sub ReadObjectData(ByVal path As String) 
    ' Create the reader.
    Dim fs As New FileStream(path, FileMode.Open)
    Dim reader As XmlDictionaryReader = _
        XmlDictionaryReader.CreateTextReader(fs, New XmlDictionaryReaderQuotas())

    ' Create the DataContractSerializer specifying the type, 
    ' root and namespace to use. The root value corresponds
    ' to the DataContract.Name value, and the namespace value
    ' corresponds to the DataContract.Namespace value.
    Dim ser As New DataContractSerializer(GetType(Person), _
        "Customer", "")

    ' Test if the serializer is on the start of the 
    ' object data. If so, read the data and write it 
    ' to the console.
    While reader.Read()
        If ser.IsStartObject(reader) Then
            Console.WriteLine("Found the element")
            Dim p As Person = CType(ser.ReadObject(reader), Person)
            Console.WriteLine("{0} {1}    id:{2}", p.FirstName, p.LastName, p.ID)
        End If

    End While


End Sub     

Universal Windows Platform
Available since 8
.NET Framework
Available since 3.0
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
Return to top