Example _php example of a singleton class in PHP

The single-instance class in PHP is useful for exchanging data and saving memory. Write a simple example.
Class 1, the single-instance class itself:

Class UTIL {  private static $instance;  Public function Get () {    if (!self:: $instance) {self      :: $instance = new UTIL ();    }    Return self:: $instance;  }  Public = ten;  Public function Change ($num) {    $this->number + = $num;  }  Public Function Getnum () {    return $this->number;  }}

Class 2, use the application class for the single-instance class described above:

Class Singlea {  private $numInst;  function __construct () {    $this->numinst = Util::get ();  }  Public function Change ($num) {    $this->numinst->change ($num);  }  Public Function Getnum () {    return $this->numinst->getnum ();}  }

Class 3, homogeneous 2:

Class Singleb {  private $numInst;  function __construct () {    $this->numinst = Util::get ();  }  Public function Change ($num) {    $this->numinst->change ($num);  }  Public Function Getnum () {    return $this->numinst->getnum ();}  }

The last place to call is:

$instA = new Singlea (), $instA->change (+), Var_dump (' Singlea CHANGED: '); Var_dump ($instA->getnum ()); $instB = New Singleb (); $instB->change ( -510); Var_dump (' Singleb CHANGED: '); Var_dump ($instB->getnum ());

The result of the final display:

String ' Singlea CHANGED: ' (length=17) int110string ' Singleb CHANGED: ' (length=17) int-400

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