遍历多维关联数组 PHP 中的每个键和值

Question

我刚刚了解了键/值对。

我试图寻找一个现有的答案，并试图了解我可以了解键/值对和关联数组。虽然这变得有点太耗时了。

我无法弄清楚如何迭代这个多维关联数组而不会出现任何错误。

$arr = array(
  'test1' => array(
    'testing 1-1' => array('testing 1-1-1', 'testing 1-1-2', 'testing 1-1-3'),
    'testing 1-2' => array('testing 1-2-1', 'testing 1-2-2', 'testing 1-2-3'),
    'testing 1-3' => array('testing 1-3-1', 'testing 1-3-2', 'testing 1-3-3')),
  'test2' => array(
    'testing 2-1' => array('testing 2-1-1', 'testing 2-1-2', 'testing 2-1-3'),
    'testing 2-2' => array('testing 2-2-1', 'testing 2-2-2', 'testing 2-2-3'),
    'testing 2-3' => array('testing 2-3-1', 'testing 2-3-2', 'testing 2-3-3')),
  'test3' => array(
    'testing 3-1' => array('testing 3-1-1', 'testing 3-1-2', 'testing 3-1-3'),
    'testing 3-2' => array('testing 3-2-1', 'testing 3-2-2', 'testing 3-2-3'),
    'testing 3-3' => array('testing 3-3-1', 'testing 3-3-2', 'testing 3-3-3')));

所以我知道 print_r 可以完美地渲染整个数组，但我想要实现的是能够获取每个可能的键和值。

我尝试通过 foreach 循环逐个回显所有字符串，但似乎单词数组本身会以某种方式导致错误。我相信这是我最合乎逻辑的方法。

foreach ($arr as $test) {
  echo $test . '<br>';
    foreach ($test as $testing1) {
      echo '&nbsp&nbsp' . $testing1 . '<br>';
      foreach ($testing1 as $testing2) {
        echo '&nbsp&nbsp&nbsp&nbsp' . $testing2 . '<br>';
    }
  }
}

虽然它会导致以下结果：

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 88
Array

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 1-1-1
    testing 1-1-2
    testing 1-1-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 1-2-1
    testing 1-2-2
    testing 1-2-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 1-3-1
    testing 1-3-2
    testing 1-3-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 88
Array

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 2-1-1
    testing 2-1-2
    testing 2-1-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 2-2-1
    testing 2-2-2
    testing 2-2-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 2-3-1
    testing 2-3-2
    testing 2-3-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 88
Array

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 3-1-1
    testing 3-1-2
    testing 3-1-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 3-2-1
    testing 3-2-2
    testing 3-2-3

Notice: Array to string conversion in /opt/lampp/htdocs/projects/form/phptest.php on line 90
  Array
    testing 3-3-1
    testing 3-3-2
    testing 3-3-3

所以我想知道我是否缺少某些东西或者这是不可能实现的？

更新：感谢您的回答。

这是我根据得到的答案使用的代码：

  foreach ($arr as $k => $test) {
    echo $k . '<br>';
      foreach ($test as $k1 => $testing1) {
        echo '&nbsp&nbsp' . $k1 . '<br>';
        foreach ($testing1 as $k2 => $testing2) {
          echo '&nbsp&nbsp&nbsp&nbsp' . $testing2 . '<br>';
      }
    }
  }

更新：

我真的很喜欢 HoldOffHunger 的建议。

<?php

    // Your Array Here

$arr = [...];

    // IterateArray() function

function IterateArray($data) {
    if(is_array($data)) {
        foreach ($data as $data_key => $data_value) {
            print("\n\n");
            print($data_key . ' :: ');
            print(IterateArray($data_value));
        }
    } else {
        print($data);
        print("\n");
    }
}

    // Call IterateArray()

IterateArray($arr);

?>

不幸的是，我对这个递归函数没有用处。对每个循环实例进行硬编码让我可以为每个嵌套循环做不同的事情。虽然（如果我错了，请纠正我）如果多维数组的每个维度都重复相同的代码，这将很有用。

Answer 1

The foreach statement 可以选择只迭代值，就像你正在做的那样，或者键和值。我怀疑这就是你要找的东西：

foreach ($arr6 as $k=>$test) {
  echo $k . '<br>';
    foreach ($test as $k1=>$testing1) {
      echo '&nbsp&nbsp' . $k1 . '<br>';
      foreach ($testing1 as $k2=>$testing2) {
        echo '&nbsp&nbsp&nbsp&nbsp' . $testing2 . '<br>';
    }
  }
}

您收到的通知是因为您尝试在数组上使用echo，这是不可能的。

Answer 2

欢迎使用 stackoverflow。 那些东西是注意事项，你不应该对数组使用 echo，而是使用 print_r($ar) 或 var_dump($ar)

foreach ($arr6 as $test) {
  print_r($test);
    foreach ($test as $testing1) {
      print_r($testing1);
      foreach ($testing1 as $testing2) {
        print_r($testing2);
    }
  }
}

您也可以像这样打印键：

foreach ($arr6 as $mykey => $test) {
  echo $mykey;
  print_r($test);

Answer 3

   $arr = array(
  'test1' => array(
    'testing 1-1' => array('testing 1-1-1', 'testing 1-1-2', 'testing 1-1-3'),
    'testing 1-2' => array('testing 1-2-1', 'testing 1-2-2', 'testing 1-2-3'),
    'testing 1-3' => array('testing 1-3-1', 'testing 1-3-2', 'testing 1-3-3')),
  'test2' => array(
    'testing 2-1' => array('testing 2-1-1', 'testing 2-1-2', 'testing 2-1-3'),
    'testing 2-2' => array('testing 2-2-1', 'testing 2-2-2', 'testing 2-2-3'),
    'testing 2-3' => array('testing 2-3-1', 'testing 2-3-2', 'testing 2-3-3')),
  'test3' => array(
    'testing 3-1' => array('testing 3-1-1', 'testing 3-1-2', 'testing 3-1-3'),
    'testing 3-2' => array('testing 3-2-1', 'testing 3-2-2', 'testing 3-2-3'),
    'testing 3-3' => array('testing 3-3-1', 'testing 3-3-2', 'testing 3-3-3')));
    foreach ($arr as $key=>$val){
        echo $key;
        foreach($val as $k=>$v){
            echo $k;
            foreach($v as $ku=>$vu){
                echo $ku;    
            }
        }
    }

你是在回显数组而不是字符串。

Answer 4

欢迎来到 SO！

我想发布一个适用于任何类型数组的解决方案，无论是 3-d、4-d 还是任何维度。那么，为什么不递归、foreach() 和is_array()？

IDEOne: Online Demo/Sandox of IterateArray()

<?php

    // Your Array Here

$arr = [...];

    // IterateArray() function

function IterateArray($data) {
    if(is_array($data)) {
        foreach ($data as $data_key => $data_value) {
            print("\n\n");
            print($data_key . ' :: ');
            print(IterateArray($data_value));
        }
    } else {
        print($data);
        print("\n");
    }
}

    // Call IterateArray()

IterateArray($arr);

?>

IterateArray()这里会打印不是数组的数据，否则会遍历数组的元素，并在这些元素上调用IterateArray()。

这个解决方案的好处是：如果你的数据结构发生变化，你的函数就不必改变了！