PHP 中数组类型和对象类型之间的区别


Difference between array type and object type in PHP

据我所知,php中的数组可以通过键和值进行设计。等

$person = array(
 'name'=>'JOSH',
 'age'=>18
);

它喜欢一个对象,但只是通过另一种方式定义。等

class info{
  $name;
  $age;
}
$person = new info();
$person->name = 'JOSH';
$person->age = 18;

我总是在PHP中使用数组,但是我的一些同事说对象类型比数组类型更好。

但是我不明白数组类型和对象类型之间有什么区别。

如果我只想在 PHP 中声明变量,有人可以告诉我这两种类型之间有什么区别吗?

有很多不同之处,但对象更强大。

在某种程度上避免重写代码,并清理代码。

认为您想对数组中的数字执行一些操作:

为了简单起见,我想您已经从数组或对象中获取了值。

            <?
            $item = array(
             'name'=>'carrot',
             'price'=>0.20,
             'stock' => 15
            );
            ?>

例如,在商店环境中,您希望获取买入价格,并更新库存。

            <?
            function getprice($item){
                return $item['price'];
            }
            function substock($item,$units){
                $item['stock'] = $item['stock'] - $units;
            }
            echo getprice($item);
            echo "<br/>";
            echo substock($item,"3");
            ?>

它将输出如下内容:0.2012

这可能是一种方法,但是我们可以对对象做什么:

            <?
            class items{
                var $name , $price, $stock;
                function __construct($in_name, $in_price, $in_stock){
                    if (!empty($in_name)){$this->name = $in_name;}
                    if (!empty($in_price)){$this->price = $in_price;}
                    if (!empty($in_stock)){$this->stock = $in_stock;}       
                } 
                function getprice(){
                    return $this->price;
                }
                function substock($units){
                    $newstock = $this->stock - $units;
                    $this->stock = $newstock;
                    return $newstock;
                }
            }

            $item = new items("carrot","0.20","15");
            echo $item->getprice();
            echo "<br/>";
            echo $item->substock("3");
            ?>

它将输出如下内容:0.2012

到目前为止,差别不大,不是吗?

但是想象一下,你想创造一个更大的东西。只是玩弄它。

现在我想加载一个只带有胡萝卜名称的项目。

然后更改方法构造,以便能够创建具有不同输入的对象:

                var $name , $price, $stock;
                function __construct($in_name, $in_price=NULL, $in_stock=NULL){
                    $args = func_num_args();
                    if ($args == 1){
                        $this->name = $in_name;
                        $this->fromdb($in_name);
                    }else{
                        if (!empty($in_name)){$this->name = $in_name;}
                        if (!empty($in_price)){$this->price = $in_price;}
                        if (!empty($in_stock)){$this->stock = $in_stock;}       
                    }
                } 
                function fromdb($name){
                    $sql = "SELECT * FROM items WHERE name = '" . $name . "'";
                    //... here we bring from database the item and put in an array called $itemdb.I                 skip this part to do it shorter. If you want, ask about and I'll post this peace and the                database objet.
                    $this -> price = $itemdb['price'];
                    $this -> stock = $itemdb['stock'];
                }
                function getprice(){
                    return $this->price;
                }
                function substock($units){
                    $newstock = $this->stock - $units;
                    $this->stock = $newstock;
                    return $newstock;
                }
            }

            $item = new items("carrot");
            echo $item->getprice();
            echo "<br/>";
            echo $item->substock("3");
            ?>

如果数据库中的值与前面的示例相同。它将输出如下内容:0.2012

但从这里你有无限的可能性。只是玩更多。提供族项目,并创建新方法。

            <?
            class items{
                var $name , $price, $stock, $family;
                function __construct($in_name, $in_price=NULL, $in_stock=NULL, $in_family=NULL){
                    $args = func_num_args();
                    if ($args == 1){
                        $this->name = $in_name;
                        $this->fromdb($in_name);
                    }else{
                        if (!empty($in_name)){$this->name = $in_name;}
                        if (!empty($in_price)){$this->price = $in_price;}
                        if (!empty($in_stock)){$this->stock = $in_stock;}       
                        if (!empty($in_family)){$this->family = $in_family;}        
                    }
                } 
                function fromdb($name){
                    $sql = "SELECT * FROM items WHERE name = '" . $name . "'";
                    //... here we bring from database the item and put in an array called $itemdb. I skip this part to do it shorter. If you want, ask about and I'll post this peace and the database objet.
                    $this -> price = $itemdb['price'];
                    $this -> stock = $itemdb['stock'];
                    $this -> family = $itemdb['family'];
                }
                function getprice(){
                    return $this->price;
                }
                function getfamily(){
                    return $this->family;
                }
                function substock($units){
                    $newstock = $this->stock - $units;
                    $this->stock = $newstock;
                    return $newstock;
                }
                function veggiesinfamily(){
                    $sql = "SELECT count(name),family FROM items WHERE family = '" . $this->family . "'";
                    //... here we bring from database the number of item of a family product in $number. I skip this part to do it shorter. If you want, ask about and I'll post this peace and the database objet.     
                    return $number;
                }
                function familystock(){
                    $sql = "SELECT SUM(stock),family FROM items WHERE family = '" . $this->family . "'";
                    //... here we bring from database the sum of stock items of a family product in $number. I skip this part to do it shorter. If you want, ask about and I'll post this peace and the database objet.     
                    return $number;
                }
            }

            $item = new items("carrot");
            echo "There are " . $item->veggiesinfamily() . $item->getfamily() . " kinds.<br/>";
            echo "There are " . $item->familystock() . " units of " . $item->getfamily();
            ?>

我们的数据库中还有一个项目:马铃薯,0.3,10,根(名称,价格,库存,家族)如果数据库中的值具有作为家庭根源和元素胡萝卜和土豆。输出将是。有2种根。根有25个单位。

等等。如果您从外部文件加载 objet 作为item_class.php,并加载为 include("item_class.php"),则可以轻松扩展脚本。

干杯。