[IronPython] Question about serialization

Paul Turbett sls at iinet.net.au
Wed Mar 26 12:55:45 CET 2008


Thanks Michael for the advice. Must appreciated. Unfortunately I hasn't 
worked out yet tho :(

I can use pickle from C# using Evaluate, or from within a Python class, 
on a "pure" Python object. However any attempt at pickling a python 
object that derives from a C# base result in an exception like this:
Cannot convert MyObject(<MyObject object at 0x000000000000002B>) to Int32

Exploring further, I came across Ops.GetDynamicType() and 
Ops.GetAttrsNames() which I thought might be helpful to get the 
attributes of an object and serialize it somehow (manually), but 
GetAttrNames requires an ICallerContext, and I can't see how to get one 
of those.

It seems that whilst serializing .NET classes is trivial, and 
serializing python classes is trivial, serializing something that 
touches both is proving quite difficult.

Any further suggestions gratefully received!

Thanks, Paul

Michael Foord wrote:
> Paul Turbett wrote:
>   
>> Hi,
>>
>> I'm using IP as a scripting engine in a C# app. I have various Python 
>> classes that derive from a C# base class, and have there own additional 
>> data & functionality.
>>
>> I would like to be able to serialize instances of the Python classes 
>> from the C# host for persistence across sessions. Using the standard 
>> BinaryFormatter with the Serializable attribute is not working - I get 
>> an error about the python class not being marked as serializable (the C# 
>> base class is marked as serializable though).
>>
>> How can I serialize python objects from C#? Should I use reflection to 
>> roll my own serializer, or is there something in one of the lesser 
>> documented assemblies like Ops I should use?
>>   
>>     
>
> Typically for serializing Python objects you would use pickle [1]. The 
> 'dumps' function returns a string (make sure you use the text protocol 
> for IronPython).
>
> You could then execute code inside the Python engine to serialize / 
> deserialize objects. I've not tried this for instances that inherit from 
> C# base classes - but it should work fine. :-)
>
> Michael Foord
> http://www.ironpythoninaction.com
>
> .. [1] http://docs.python.org/lib/module-pickle.html
>
>   
>> I'm using IP 1.1.1 (but will move to 2.0 if that will help). Any 
>> pointers & advice greatly appreciated!
>>
>> Thanks, Paul
>> _______________________________________________
>> Users mailing list
>> Users at lists.ironpython.com
>> http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
>>   
>>     
>
> _______________________________________________
> Users mailing list
> Users at lists.ironpython.com
> http://lists.ironpython.com/listinfo.cgi/users-ironpython.com
>
>   

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/ironpython-users/attachments/20080326/5b23c30b/attachment.html>


More information about the Ironpython-users mailing list