Greetings from Syncfusion!!
We understand your query about triggering the “select” event while using with check or uncheck all methods. In a much simple data say 10 items, it will work fine and we can trigger “select” event for all the items but when it comes to, say 10000 items, it is not feasible to trigger an event 10000 times. So, may we know your purpose or need of the “select” event, so that we can provide a solution or work around for your need?