Teacher, please look at this place again. It's<button type="button" class="btn btn-default" id="fav" user_id={$Think.session.user_id} art_id={$artInfo.id}>Collection</button>here The user_id is the id of the logged in user. The background can also directly determine whether this value exists. If you don’t have it, you can’t collect it.
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Teacher, why is this value not determined directly at the front desk?
Yes