PHP5变量范围和类构造 - PHP5 variable scope and class construction

PHP5 variable scope and class construction

本文关键字：变量范围 PHP5 | 更新日期: 2023-09-27

我在访问类中的变量时遇到问题。。。

class getuser {
    public function __construct($id) {
        $userquery = "SELECT * FROM users WHERE id = ".$id."";
        $userresult = mysql_query($userquery);
        $this->user = array();
        $idx = 0;
        while($user = mysql_fetch_object($userresult)){
           $this->user[$idx] = $user;
           ++$idx;
        }
    }
}

我在一个全局"classes"文件中设置这个类，稍后我将用户id传递到以下脚本中：

$u = new getuser($userid);
    foreach($u->user as $user){
        echo $user->username;
    }

我希望这能给我用户的名字，但事实并非如此，我哪里错了？！

感谢

请将您的用户成员定义为类中的公共成员，如下

class getuser {
    public $user = null;
    //...
}

为了访问类属性，您必须将其声明为公共或实现getter和setter（第二种解决方案更可取）

class A {
  public $foo;
  //class methods
}
$a = new A();
$a->foo = 'whatever';

带有getter和setter，每个属性一个

class B {
  private $foo2;
  public function getFoo2() {
    return $this->foo2;
  }
  public function setFoo2($value) {
    $this->foo2 = $value;
  }
}
$b = new B();
$b->setFoo2('whatever');  
echo $b->getFoo2();

在您的示例中：

class getuser {
    private $user;
    public function __construct($id) {
        $userquery = "SELECT * FROM users WHERE id = ".$id."";
        $userresult = mysql_query($userquery);
        $this->user = array();
        $idx = 0;
        while($user = mysql_fetch_object($userresult)){
           $this->user[$idx] = $user;
           ++$idx;
        }
    }
    /* returns the property value */
    public function getUser() {
      return $this->user;
    }
    /* sets the property value */
    public function setUser($value) {
      $this->user = $value;
    }
}

$u = new getuser($userid);
$users_list = $u->getUser();
    foreach($users_list as $user) {
        echo $user->username;
    }