Regarding the data binding issue that you have encountered - you need to access the field from the DataItem
of the currently evaluated item in the ItemDataBoundHandler. Please consider the following implementation :
As for your other question, by design if the selection mode is set to single, the RadAutoCompleteBox should not append the semi column at the end of the newly added entry. Could you please specify the version of our controls that you are currently using? In addition, here is a video, demonstrating the behavior at my end :
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