How the methods in the PHP class access other methods in the same way

How do the methods in the PHP class access other methods in the same way?
Class Action {

function A () {
Function B () {

}
}

Function C () {
How does this call the B method in the A method???
}

}

------Solution--------------------
Do not write like this, what bothered problem, must be so toss it? Say it, and we'll help you figure out a way. Don't try to chase this niu Jiao Jian
------Solution--------------------
It's no big deal.

PHP code

class Action {function A () {function B () {Echo    123;    }} function C () {//This is how to call the B method in the A method???  b (); }} $p = new Action; $p->a (); $p->c ();//123b ()//123 
------Solution--------------------
 Hey, you can make mistakes sometimes. 
 
 You want the C function to use the B function, so you have to initialize a () before you use it. 
 Because a () inside PHP is gray to PHP does not know that a () has a B () 
 So you do not initialize a () with B () will definitely go wrong. The 
 correct call is first A () in C (). 
------Solution--------------------
 PHP is a major feature, but also a tragedy is that the function definition has no scope, where all the line, as long as it appears. 
------Solution--------------------
 
   
   

    
     PHP code 
    
    
class actio        n {function A () {$this->b ();        }//Pull out the B () function. function B () {} function C () {//) How do I call the B method in the A method???    $this->b (); }} 
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