Type Operators - Miscellanies (continuously updated)

instanceof

is used to determine a Whether a PHP variable belongs to an instance of a certain class class

can also be used to determine whether a variable is an instance of a subclass inherited from a certain parent class

instanceof can also be used to determine whether a variable is an instance of an object that implements a certain interface

The above introduces the type operator - Miscellaneous Notes (Continuous Update), including updates and persistence. I hope it will be helpful to friends who are interested in PHP tutorials.