Is there a way to get the value of the data bound property while in ConvertBack() of IValueconverter class?

What I’d like to achieve is updating a property in my code behind according to a text box on my UI AND the value already in the code behind property. In ConvertBack() I’d love to have access to the code behind property and the textbox contents.

I’ve tried adding a property to my converter class that can be bound to the property in my code behind but it’s been a real headache trying to get it to work the way I want it to.

Hopefully this is simple enough to understand without some example code. Thanks.

Hopefully this is simple enough to understand without some example code. Thanks.
I think an example would help.

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