将php变量从方法传递到外部类

class MyClass {
    private $myVariable;

    public function myMethod() {
        $this->myVariable = "Hello, World!";
    }

    public function anotherMethod() {
        echo $this->myVariable;
    }
}

$obj = new MyClass();
$obj->myMethod();
$obj->anotherMethod(); // 输出 "Hello, World!"

class MyClass {
    public function myMethod() {
        $myVariable = "Hello, World!";
        return $myVariable;
    }
}

$obj = new MyClass();
$variable = $obj->myMethod();
echo $variable; // 输出 "Hello, World!"

class MyClass {
    public function myMethod(&$myVariable) {
        $myVariable = "Hello, World!";
    }
}

$obj = new MyClass();
$variable = "";
$obj->myMethod($variable);
echo $variable; // 输出 "Hello, World!"