Learning_abc wrote:
SelectedValue="{Binding codePartsTypeID,Mode=TwoWay}"/>
Does it your DataContext has codePartsTypeID as property?
You can add some debug converters to check it you get value (other than null). You have to check your Output Window too as all the Binding Errors are thrown there.
For Debugging DataBinding, you can read
Debugging Trick in XAML DataBinding[
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