serialization

[Perecli Manole]

I have a class that has been serialized and saved to disk. I am trying to
deserialize it back into the same class which now has an extra private
member. It will not deserialize because its signature has changed so I
added:

Protected Sub New(ByVal info As SerializationIn fo, ByVal context As
StreamingContex t)
End Sub

to my new class so that I can specify custom deserialization however it does
not get called by the deserialization formatter if I don't specify that the
class implements iSerializable. When I do implement iSerializable in my new
class then the class signature no longer matches the old class so an error
gets raised. Seems like I am stuck. Maybe if I had implemented iSerializable
from the beginning in the old class this might have worked but what should I
do now?

Perry

[Jay B. Harlow [MVP - Outlook]]

Perecli,
One of the following 3 part MSDN Magazine column on Serialization covers
this problem and how to correct it!

http://msdn.microsoft.com/msdnmag/issues/02/04/net/
http://msdn.microsoft.com/msdnmag/issues/02/07/net/
http://msdn.microsoft.com/msdnmag/issues/02/09/net/

I hope you read all three, as they are invaluable for implementing
Serialization in .NET!

You are correct in needing to implement ISerializable and give the special
constructor, in addition to implementing ISerializable you need to 'Override
the type when deserializing', which is covered in the 3rd article. It
involves creating a new binder class that changes the type for version 1.0
objects to version 2.0 object.

Hope this helps
Jay

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e$******** ******@TK2MSFTN GP11.phx.gbl...

I have a class that has been serialized and saved to disk. I am trying to
deserialize it back into the same class which now has an extra private
member. It will not deserialize because its signature has changed so I
added:

Protected Sub New(ByVal info As SerializationIn fo, ByVal context As
StreamingContex t)
End Sub

to my new class so that I can specify custom deserialization however it does not get called by the deserialization formatter if I don't specify that the class implements iSerializable. When I do implement iSerializable in my new class then the class signature no longer matches the old class so an error
gets raised. Seems like I am stuck. Maybe if I had implemented iSerializable from the beginning in the old class this might have worked but what should I do now?

Perry

[Perecli Manole]

Yes, I have read all three articles on your previous recomendation. This is
what got me so far but it is still not working. This is how my
deserialization binder class looks:

Private Class VersionDeserial izationBinder
Inherits SerializationBi nder

Public Overrides Function BindToType(ByVa l assemblyName As
String, ByVal typeName As String) As Type
Return Type.GetType(St ring.Format("{0 }, {1}", typeName,
Reflection.Asse mbly.GetExecuti ngAssembly.Full Name))
End Function
End Class

Still have the same problem mentioned in my initial post.

Perry

"Jay B. Harlow [MVP - Outlook]" <Ja********@ema il.msn.com> wrote in message
news:eA******** *****@TK2MSFTNG P11.phx.gbl...

Perecli,
One of the following 3 part MSDN Magazine column on Serialization covers
this problem and how to correct it!

http://msdn.microsoft.com/msdnmag/issues/02/04/net/
http://msdn.microsoft.com/msdnmag/issues/02/07/net/
http://msdn.microsoft.com/msdnmag/issues/02/09/net/

I hope you read all three, as they are invaluable for implementing
Serialization in .NET!

You are correct in needing to implement ISerializable and give the special
constructor, in addition to implementing ISerializable you need to 'Override the type when deserializing', which is covered in the 3rd article. It
involves creating a new binder class that changes the type for version 1.0
objects to version 2.0 object.

Hope this helps
Jay

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e$******** ******@TK2MSFTN GP11.phx.gbl...

I have a class that has been serialized and saved to disk. I am trying to deserialize it back into the same class which now has an extra private
member. It will not deserialize because its signature has changed so I
added:

Protected Sub New(ByVal info As SerializationIn fo, ByVal context As
StreamingContex t)
End Sub

to my new class so that I can specify custom deserialization however it does

not get called by the deserialization formatter if I don't specify that

the

class implements iSerializable. When I do implement iSerializable in my

new

class then the class signature no longer matches the old class so an error gets raised. Seems like I am stuck. Maybe if I had implemented

iSerializable

from the beginning in the old class this might have worked but what

should I

do now?

Perry

[Jay B. Harlow [MVP - Outlook]]

Perecli,
Not sure what to offer, as your code does not appear at all like the sample
in Figure 3 of article 3.

Are all the types you are deserializing in the same assembly as the
VersionDeserial izationBinder class?

What you may want to do is put a break point in BindToType to see what is
coming in and what is going out, just to be certain that you have
implemented it correctly.

Hint, I suspect the routine is called for types in the System namespace,
such as System.String.

Hope this helps
Jay

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e5******** ******@tk2msftn gp13.phx.gbl...

Yes, I have read all three articles on your previous recomendation. This is what got me so far but it is still not working. This is how my
deserialization binder class looks:

Private Class VersionDeserial izationBinder
Inherits SerializationBi nder

Public Overrides Function BindToType(ByVa l assemblyName As
String, ByVal typeName As String) As Type
Return Type.GetType(St ring.Format("{0 }, {1}", typeName,
Reflection.Asse mbly.GetExecuti ngAssembly.Full Name))
End Function
End Class

Still have the same problem mentioned in my initial post.

Perry

"Jay B. Harlow [MVP - Outlook]" <Ja********@ema il.msn.com> wrote in message news:eA******** *****@TK2MSFTNG P11.phx.gbl...

Perecli,
One of the following 3 part MSDN Magazine column on Serialization covers
this problem and how to correct it!

http://msdn.microsoft.com/msdnmag/issues/02/04/net/
http://msdn.microsoft.com/msdnmag/issues/02/07/net/
http://msdn.microsoft.com/msdnmag/issues/02/09/net/

I hope you read all three, as they are invaluable for implementing
Serialization in .NET!

You are correct in needing to implement ISerializable and give the special

constructor, in addition to implementing ISerializable you need to

'Override

the type when deserializing', which is covered in the 3rd article. It
involves creating a new binder class that changes the type for version 1.0 objects to version 2.0 object.

Hope this helps
Jay

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e$******** ******@TK2MSFTN GP11.phx.gbl...

I have a class that has been serialized and saved to disk. I am trying to deserialize it back into the same class which now has an extra private
member. It will not deserialize because its signature has changed so I
added:

Protected Sub New(ByVal info As SerializationIn fo, ByVal context As
StreamingContex t)
End Sub

to my new class so that I can specify custom deserialization however

it does

not get called by the deserialization formatter if I don't specify

that the

class implements iSerializable. When I do implement iSerializable in

my new

class then the class signature no longer matches the old class so an

error gets raised. Seems like I am stuck. Maybe if I had implemented

iSerializable

from the beginning in the old class this might have worked but what

should

I

do now?

Perry

[Perecli Manole]

> Not sure what to offer, as your code does not appear at all like the
sample

in Figure 3 of article 3.
The sample shows how to deserialize a class with one name into a class with
a differet name. This will not work for my application because all the code
in my app references the class by name.

For example. I serialized a class with the name "MyClass" and saved it to
disk. After this I modified "MyClass" by adding a private member. Now I want
to deserialize the class on disk back into the same class "MyClass", not
another class as is shown in the example.
Are all the types you are deserializing in the same assembly as the
VersionDeserial izationBinder class?
Yes
What you may want to do is put a break point in BindToType to see what is
coming in and what is going out, just to be certain that you have
implemented it correctly.
I have done this and all is OK. The version of the old class is changed to
that of the current assembly.
Hint, I suspect the routine is called for types in the System namespace,
such as System.String.
The problem is that when I add "Implements ISerializable" to my new class,
with no other changes as compared to the old class that was serialized. The
deserializer complains that it can't deserialize it to the new class. Keep
in mind that my old class did not implement ISerializable.

Perry
"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e5******** ******@tk2msftn gp13.phx.gbl...

Yes, I have read all three articles on your previous recomendation. This

is

what got me so far but it is still not working. This is how my
deserialization binder class looks:

Private Class VersionDeserial izationBinder
Inherits SerializationBi nder

Public Overrides Function BindToType(ByVa l assemblyName As
String, ByVal typeName As String) As Type
Return Type.GetType(St ring.Format("{0 }, {1}", typeName,
Reflection.Asse mbly.GetExecuti ngAssembly.Full Name))
End Function
End Class

Still have the same problem mentioned in my initial post.

Perry

"Jay B. Harlow [MVP - Outlook]" <Ja********@ema il.msn.com> wrote in

message

news:eA******** *****@TK2MSFTNG P11.phx.gbl...

Perecli,
One of the following 3 part MSDN Magazine column on Serialization covers this problem and how to correct it!

http://msdn.microsoft.com/msdnmag/issues/02/04/net/
http://msdn.microsoft.com/msdnmag/issues/02/07/net/
http://msdn.microsoft.com/msdnmag/issues/02/09/net/

I hope you read all three, as they are invaluable for implementing
Serialization in .NET!

You are correct in needing to implement ISerializable and give the special constructor, in addition to implementing ISerializable you need to

'Override

the type when deserializing', which is covered in the 3rd article. It
involves creating a new binder class that changes the type for version 1.0 objects to version 2.0 object.

Hope this helps
Jay

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e$******** ******@TK2MSFTN GP11.phx.gbl...
> I have a class that has been serialized and saved to disk. I am trying

to

> deserialize it back into the same class which now has an extra

private > member. It will not deserialize because its signature has changed so I > added:
>
> Protected Sub New(ByVal info As SerializationIn fo, ByVal context As
> StreamingContex t)
> End Sub
>
> to my new class so that I can specify custom deserialization however

it does
> not get called by the deserialization formatter if I don't specify that the
> class implements iSerializable. When I do implement iSerializable in my new
> class then the class signature no longer matches the old class so an

error

> gets raised. Seems like I am stuck. Maybe if I had implemented
iSerializable
> from the beginning in the old class this might have worked but what

should

I
> do now?
>
> Perry
>
>

[Jay B. Harlow [MVP - Outlook]]

Perecli,
Not sure what to offer, I gave you all the tricks I know on the subject.

Asking in either microsoft.publi c.dotnet.framew ork or
microsoft.publi c.dotnet.framew ork.clr might find someone with more knowledge
on Serialization.

Good luck,
Jay

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e5******** ******@TK2MSFTN GP12.phx.gbl...

Not sure what to offer, as your code does not appear at all like the sample

in Figure 3 of article 3.

The sample shows how to deserialize a class with one name into a class

with a differet name. This will not work for my application because all the code in my app references the class by name.

For example. I serialized a class with the name "MyClass" and saved it to
disk. After this I modified "MyClass" by adding a private member. Now I want to deserialize the class on disk back into the same class "MyClass", not
another class as is shown in the example.

Are all the types you are deserializing in the same assembly as the
VersionDeserial izationBinder class?
Yes

What you may want to do is put a break point in BindToType to see what is

coming in and what is going out, just to be certain that you have
implemented it correctly.

I have done this and all is OK. The version of the old class is changed to
that of the current assembly.

Hint, I suspect the routine is called for types in the System namespace,
such as System.String.

The problem is that when I add "Implements ISerializable" to my new class,
with no other changes as compared to the old class that was serialized.

The deserializer complains that it can't deserialize it to the new class. Keep
in mind that my old class did not implement ISerializable.

Perry

"Perecli Manole" <Pe*****@dslext reme.com> wrote in message
news:e5******** ******@tk2msftn gp13.phx.gbl...

Yes, I have read all three articles on your previous recomendation. This

is

what got me so far but it is still not working. This is how my
deserialization binder class looks:

Private Class VersionDeserial izationBinder
Inherits SerializationBi nder

Public Overrides Function BindToType(ByVa l assemblyName As
String, ByVal typeName As String) As Type
Return Type.GetType(St ring.Format("{0 }, {1}",

typeName, Reflection.Asse mbly.GetExecuti ngAssembly.Full Name))
End Function
End Class

Still have the same problem mentioned in my initial post.

Perry

"Jay B. Harlow [MVP - Outlook]" <Ja********@ema il.msn.com> wrote in message

news:eA******** *****@TK2MSFTNG P11.phx.gbl...
> Perecli,
> One of the following 3 part MSDN Magazine column on Serialization

covers > this problem and how to correct it!
>
> http://msdn.microsoft.com/msdnmag/issues/02/04/net/
> http://msdn.microsoft.com/msdnmag/issues/02/07/net/
> http://msdn.microsoft.com/msdnmag/issues/02/09/net/
>
> I hope you read all three, as they are invaluable for implementing
> Serialization in .NET!
>
> You are correct in needing to implement ISerializable and give the

special

> constructor, in addition to implementing ISerializable you need to
'Override
> the type when deserializing', which is covered in the 3rd article. It > involves creating a new binder class that changes the type for version 1.0

> objects to version 2.0 object.
>
> Hope this helps
> Jay
>
> "Perecli Manole" <Pe*****@dslext reme.com> wrote in message
> news:e$******** ******@TK2MSFTN GP11.phx.gbl...
> > I have a class that has been serialized and saved to disk. I am trying to
> > deserialize it back into the same class which now has an extra private > > member. It will not deserialize because its signature has changed

so I > > added:
> >
> > Protected Sub New(ByVal info As SerializationIn fo, ByVal context

As > > StreamingContex t)
> > End Sub
> >
> > to my new class so that I can specify custom deserialization however it

> does
> > not get called by the deserialization formatter if I don't specify

that

> the
> > class implements iSerializable. When I do implement iSerializable

in my

> new
> > class then the class signature no longer matches the old class so

an error
> > gets raised. Seems like I am stuck. Maybe if I had implemented
> iSerializable
> > from the beginning in the old class this might have worked but what should
> I
> > do now?
> >
> > Perry
> >
> >
>
>