The observed by you behavior is an expected one with the current implementation of RadComboBox. When the FindFullMatchIndex
returns -1 the first item is expected to be highlighted and currently this is how the control is expected to work and there isn't any approach to use in order to modify or alter that behavior. Some more information concerning the FindFullMatchIndex
and how it behaves you could find on the following link from our documentation:
We hope the provided information will be helpful for you.
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