class pig{
//猪的属性
public $name;
public $weight;
public $color;
public $age;
//成员方法
public function addweight($a){
$this->weight=$weight+$a;
}
}
$pig1=new pig();
$pig1->weight=100;
$pig1->addweight(5);
echo $pig1->weight;
这样的结果是Notice: Undefined variable: weight in D:\WWW\lianxi.php on line 10
5然后我把 $this->weight=$weight+$a;换成$this->weight+=$a;结果就是正确的105,我想问的是为什么$this->weight=$weight+$a这样是不可以的,求解答,谢谢
//猪的属性
public $name;
public $weight;
public $color;
public $age;
//成员方法
public function addweight($a){
$this->weight=$weight+$a;
}
}
$pig1=new pig();
$pig1->weight=100;
$pig1->addweight(5);
echo $pig1->weight;
这样的结果是Notice: Undefined variable: weight in D:\WWW\lianxi.php on line 10
5然后我把 $this->weight=$weight+$a;换成$this->weight+=$a;结果就是正确的105,我想问的是为什么$this->weight=$weight+$a这样是不可以的,求解答,谢谢
这样才是正确的
//猪的属性
public $name;
public $weight;
public $color;
public $age;
//成员方法
public function addweight($a){
$this->weight=$weight+$a; 不能这么写
}
}
$pig1=new pig();
$pig1->weight=100;
$pig1->addweight(5);
echo $pig1->weight;