Any chance that changing one property on an entity through databinding would effect the databinding on another control that binds to a different property?

Example:

I have an entity "ActualJobTask" that has its properties bound to various controls on a form. In this case we'll say that the properties are "MetContract", "CrewName", and "ConsistName".

MetContract is bound to a checkbox CrewName is bound to a textbox ConsistName is bound to a textox

It's random and sometimes difficult to reproduce, but if I change one property via its bound control one or both of the others may blank out. Also, if I then check the underlying property values, it shows them as empty strings (at least for the string properties). In the call stack, the last code that gets executed before the controls get cleared (not counting "non-user" code) is the entitybase property changed event firing like "ActualJobTaskEntityBase_MetContractChanged.

I can't find any other information that would be helpful; it's just simple databinding. However, I was wondering when/if/somehow the entity gets refreshed and databound values that haven't been persisted yet get written over for some reason.

I'll continue to work on it and update this with more info if/when I find it...

Thanks,

Jeff...

Simple databinding on a form is controlled by the form's CurrencyManager. It binds to all changed events of the properties which are bound to controls and keeps track of values of properties which are bound to multiple controls. This CurrencyManager can sometimes go bezerk in situations where binding is setup AGAIN, in a handler. Check that you do not setup it more than once.

Also, the entity only gets refreshed when its state is OutOfSync. This is only the case when the entity is Saved and not refetched yet. Even if it gets refetched, the bound properties will just change, so it shouldn't clear the contents.

Set breakpoint in every eventhandler you might have setup with the controls and the entity (in the form class) and check which code is called when. Check if the actual CurrentValue of the Field object in myentity.Fields(index) is indeed empty or not.

Not sure if this will fix your problem or not Jeff, but I find that I need to call:

    MyControl.DataBindings.Clear()

for each bound control in the form close event. If I don't, every time I open the form the controls' bindings gets 'confused'.

Cheers,

Padgett

Hey there. Actually I do call Control.DataBindings.Clear however I do it before I call Control.DataBindings.Add everytime.

My problem went away and I'm not sure why. I was in the process of reworking the form and ended up changing the location of the bound object. Originally, the bound object was an exposed property of another object. I ended up copying in the object to a local variable and bound directly to it. However, it doesn't seem as if that should have made a difference (being a reference type and all).

I didn't change any other binding code...oh well, its resolved. I'll let you know if I run into it again. Thanks for the help.

Jeff...