数组数据无法迭代(PHP)

Question

注意：这只是测试代码，因为我正在学习 PHP，所以没有实际意义。

基本上，我要问的是如何将对象数组转换回我可以使用的形式。

问题：我创建了一个包含 8 种不同农产品的新对象数组。我想将它们写入 .txt 文件，然后在编码后重新访问数组对象数据。目前，我收到“尝试获取非对象的属性 'price'”的错误，我不确定为什么。

class Item{
    public $name;
    public $price;

    function __construct( $name, $price ){
        $this->name = $name;
        $this->price  = $price;
    }
};

$produceList = [
    new Item("bananas", 0.59),
    new Item("grapes", 2.99),
    new Item("apples", 1.49),
    new Item("pears", 1.39),
    new Item("lettuce", 0.99),
    new Item("onions", 0.79),
    new Item("potatoes", 0.59),
    new Item("peaches", 1.59)
];

file_put_contents("ProducePrice.txt", ""); //clear file for testing
$file = fopen("ProducePrice.txt", "a");
fwrite($file, json_encode($produceList));
fclose($file);

$read = file("ProducePrice.txt");

foreach($read as $i){
  echo $i->price; //error: Trying to get property 'price' of non-object
};

这就是 ProducePrice.txt 的样子：

[ {"name":"bananas","price":0.59},{"name":"grapes","price":2.99},{"name":"apples","price":1.49},{"name":"pears","price":1.39},{"name":"lettuce","price":0.99},{"name":"onions","price":0.79},{"name":"potatoes","price":0.59},{"name":"peaches","price":1.59} ]

Answer 1

Nvm，想通了。

class Item{
    public $name;
    public $price;

    function __construct( $name, $price ){
        $this->name = $name;
        $this->price  = $price;
    }
};
$produceList = [
  new Item("bananas", 0.59),
  new Item("grapes", 2.99),
  new Item("apples", 1.49),
  new Item("pears", 1.39),
  new Item("lettuce", 0.99),
  new Item("onions", 0.79),
  new Item("potatoes", 0.59),
  new Item("peaches", 1.59)
];
file_put_contents("ProducePrice.txt", json_encode($produceList)); //restart

$test = json_decode(file_get_contents("ProducePrice.txt"), true);


echo gettype($test);

foreach($test as $i){
  echo $i["name"];
};

Answer 2

发生这种情况是因为您试图从 Object 中调用一些东西并且您的文件是文本而不是从中调用某些东西的对象。

$read = file("ProducePrice.txt"); // Not an Object Just array have a one Index

尝试

print_r($read); // To See Your Info More Readable to know what I mean

数组数据无法迭代(PHP)

Array Data Unable to be Iterated Through (PHP)

php

arrays

encode

decode