Changing ComboBox State from within SelectedIndexChanged

I often have a situation where within the SelecteIndexChanged event of a
ComboBox, I want to change the index again. For example, a changed index
triggers an action that can fail, in which case I want to return the index of
the combobox to its previous value. However, doing this within the event
handler of course triggers another invocation of the event handler. Is there
a standard idiom for handling this? I mean other than temporarily disabling
the event handler, which seems pretty kludgey. Thanks.
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