The difference between a PHP value and a pass-through and a pass-through address

Pass value,
is to assign the value of the argument to the row parameter
Then the modification of the row parameter does not affect the value of the argument

Send Address
is a special way of passing a value, except that he passes an address, not an ordinary one, such as an int.
After the address is passed, both the argument and the row parameter point to the same object

Pass Reference
The real way to pass parameters in an address
After passing, both the row and argument are the same object , except that their names are different.
Modifications to the row parameters affect the value of the argument

Consider only value passing and referencing:
The so-called value passing means that only the value of the object is passed to the target object, which is equivalent to copy; The system will re-open an identical memory space for the target object.
The so-called reference, that is, to pass an object's in-memory address to the target object, is equivalent to making the target object and the original object correspond to the same memory storage space . In this case, the data in memory will change if the target object is modified.

The difference between a PHP value and a pass-through and a pass-through address