為什么這樣寫代碼是錯(cuò)的啊
<?php
class car{
?public $speed=0;
?public function speedUp(){
??return $speed+10;
?}
?$car=new Car();
?$car->speedUP()
?echo $car->speed;
??>
<?php
class car{
?public $speed=0;
?public function speedUp(){
??return $speed+10;
?}
?$car=new Car();
?$car->speedUP()
?echo $car->speed;
??>
2017-03-18
舉報(bào)
2017-07-11
因?yàn)檫@句代碼return $speed+10;他返回的是$speed +10 的值,而下面你調(diào)用輸出的是?
?echo $car->speed;的值,改的話方法里可以這么寫
public function speedUp()
{
????$speed = $speed + 10;
????return $speed;
}
2017-05-05
你這么寫思路不夠簡(jiǎn)潔,邏輯有問(wèn)題啊
2017-03-18
class Car{//大寫
? ? public ?$speed=0;
? ? public function speedUp(){
? ? ? ? return $this->speed+=10;
? ? }
}//您打少了花括號(hào)
? ? $c = new Car();
? ? $c->speedUp(); //注意大小寫
? ? echo $c->speed;
這樣就行了
2017-03-18
問(wèn)題在類里面,return $speed+10;這里返回值雖然加了10,但是變量speed本身并沒(méi)有改變,所以最后輸出的還是0