Serialization of Enums

[Mike]

I'm a bit stumped on some odd behaviour I've found when serializing a class
that has both Enumeration and Object fields.

My class is as follows:

Public Class TestClass
Public Value1 As Object
Public Value2 As Microsoft.Win32.RegistryHive
End Class

and if I serialize the following object:

Dim objTestObject As New TestClass
objTestObject.Value1 = Microsoft.Win32.RegistryHive.LocalMachine
objTestObject.Value2 = Microsoft.Win32.RegistryHive.ClassesRoot

I get this xml out, which is what I expected:

<?xml version="1.0" encoding="utf-8"?>
<TestClass xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Value1 xsi:type="RegistryHive">LocalMachine</Value1>
<Value2>ClassesRoot</Value2>
</TestClass>

*However*, if I add a remove the Value2 field definition from the class so
that it reads:

Public Class TestClass
Public Value1 As Object
End Class

then Value1 ceases to be of xsi:type="RegistryHive" and I get this ixml
nstead:

<?xml version="1.0" encoding="utf-8"?>
<TestClass xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Value1 xsi:type="xsd:int">-2147483646</Value1>
</TestClass>

when what I really want is:

<?xml version="1.0" encoding="utf-8"?>
<TestClass xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<Value1 xsi:type="RegistryHive">LocalMachine</Value1>
</TestClass>

Does anyone know how to rig the XML serialization attributes on TestClass so
that it still serializes Value1 as "<Value1
xsi:type="RegistryHive">LocalMachine</Value1>" even if the Value2 field is
absent from the class definition? Bearing in mind that Value1 still needs to
be an Object field.

Many thanks in advance,

Mike