（De）在VB.Net中序列化

Question

我写了一个类（只包含属性）。代码缩短了，这里只是我想要做的代码的一部分：

    Public Class test
        Public Overrides Function ToString() As String
            'Das Objekt lebensmittel serialisieren
            Dim ser As New Xml.Serialization.XmlSerializer(Me.GetType)
            Dim sw As New IO.StringWriter
            ser.Serialize(sw, Me)
            Return sw.tostring
        End Function

    Public Sub New()

    End Sub

    Public Sub New(ByVal t As String)
        Dim deser As New Xml.Serialization.XmlSerializer(Me.GetType)
        Dim ms As New IO.MemoryStream(System.Text.Encoding.Unicode.GetBytes(t))
        Me = CType(deser.Deserialize(ms), test) 'This throws an error
    End Sub
End Class

我想要做的是重载New（）运算符并将字符串反序列化为此类，如：

Dim x As New test(string)

我该怎么做？标记的行在Sub New中抛出错误。