PHP如何获取数组的键值

Question

我在尝试使用数组结构的数组时有以下设置。 我不确定在数组数组中找到键值后如何获取键值。

$testboat = 'smallest boat';
$allboats = array(40=>array(1=>'big boat',
                            2=>'bigger boat'
                      ),
                  30=>array(1=>'little boat',
                           2=>'tiny boat',
                           3=>'smallest boat'));

foreach($allboats as $boats){
    foreach($boats as $boat){
       if($testboat == $boat) {

       /*looking to echo the key or value 30; */

      }  

   }
}

Answer 1

使用foreach()的$key => $value语法。 另外，无需遍历内部数组：

foreach($allboats as $key => $boats){
    if(in_array($testboat, $boats)) {
        echo $key;
        break; //if you want to stop after found
    }
}

如果要获取外键和内键：

foreach($allboats as $key => $boats){
    if(($inner_key = array_search($testboat, $boats)) !== false) {
        echo "$key and $inner_key";
        break; //if you want to stop after found
    }
}

Answer 2

$testboat = 'smallest boat';
$allboats = array(40=>array(1=>'big boat',
                            2=>'bigger boat'
                      ),
                  30=>array(1=>'little boat',
                           2=>'tiny boat',
                           3=>'smallest boat'));

foreach($allboats as $id => $boats){
    //$id will be 40, then 30
    foreach($boats as $id2 => $boat){
        //$id2 will be 1,2...
       if($testboat == $boat) {
       echo $id . '-' . $id2;
       /*looking to echo the key or value 30; */

      }  
   }
}

Answer 3

您必须执行以下操作：

foreach($allboats as key1 => $boats){
    foreach($boats as key2 => $boat){