What if the change event is not triggered when Angular2 assigns a value to the cascading Select?

now the three-level cascade select has been done, but it is found that the change event will not be triggered when assigning values in onInit. How do you handle it in use?

Mar.05,2021

(change) = "selectChange ($event)" change to (ngModelChange) = "selectChange ($event)"
then console.log (event); will do

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