NHibernate proxy causes data binding problems

Question

I have a gridview related to the result of a nhibernate request. If the first item in the list is edited, the following exception is thrown:

System.Reflection.TargetException: Object does not match target type

The problem seems to be caused by the fact that data binding cannot process the first item in the list, which is a subtype of the other items in the list.

What is a good / right way to solve this problem? Currently, I had to disable nhibernates proxying.

Edit: I have a few more solutions:

• Clone everything in the list ( http://steve-fair-dev.blogspot.com/2007/08/databind-object-does-not-match-target.html ) - this does not work for me, since the object does not implement ICloneable
• change the order of the items in the list so that the proxy server is not the first ( http://community.devexpress.com/forums/t/30797.aspx ) - it’s so hacky, I don’t think I can overcome this minimum!

But none of them are feeling well, though ...

Answer 1

Is the reason because of the proxy object in the list (from lazy loading) or because the list is not homogeneous (contains several types, even if they belong to the same class hierarchy)? The problem with heterogeneous datasets is a known limitation. See this and this .

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Answer 2

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Answer 3

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Answer 4

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Answer 5

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