About references (&) in PHP

PHP references (add & symbols before variables or functions, objects, etc.)

The reference in PHP means: Different names access the same variable content.

There is a difference between the pointers in the C language. The pointer inside the C language stores the address where the contents of the variable are stored in memory.

A reference to a variable

PHP references allow you to use two variables to point to the same content

Invocation of a function's address

Address call I'm not going to say much. Directly below the code

 
  "; echo $b;//Output 101?>

It is important to note that here Test (1), the words will be wrong, reason to think.

A reference to the function returns

Look at the code first

The following explanation:

In this way $a=test (); The result is not a function reference return, which is no different from the normal function call, as for the reason:

This is the PHP rule, PHP rules through $a=&test (); The way to get is to return the reference to the function. As for what is a reference return (the PHP manual says that reference return is used when you want to use a function to find out which variable the reference should be bound to.) I didn't read this bullshit.

This is explained by the example above:

$a =test () call the function, just assign the value of the function to $ A, and $ A does nothing to affect the $b in the function and call the function by $a=&test (), his function is to return the memory address of the $b variable in the $b with the The memory address of a variable points to the same place, which produces the equivalent effect ($a =&b;) So changing the value of $ A also changes the value of the $b so that it executes $a =&test (); $a = 5; Later, the value of the $b becomes 5

This is to let everyone understand that the function reference returns only use static variables, in fact, the function of the reference return is used in the object.

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