Construct a mapping (in the form of key-value) from a multidimensional array or array
The mapping relationship is set by specifying the corresponding key value or attribute name through the "$from" and "$to" parameters.
Of course, you can also further group mapping based on the grouping field "$group".
For example:
$array = [ ['id' => '123', 'name' => 'aaa', 'class' => 'x'], ['id' => '124', 'name' => 'bbb', 'class' => 'x'], ['id' => '345', 'name' => 'ccc', 'class' => 'y'], ];
The above array executes the following method
还可以添加第四个参数 $result = ArrayHelper::map($array, 'id', 'name', 'class');
The result is
[ 'x' => [ '123' => 'aaa', '124' => 'bbb', ], 'y' => [ '345' => 'ccc', ], ]
The following is the detailed code of the map method
/**
* @paramarray $array
* @param string|Closure $from
* @param string|Closure $to
* @param string|Closure $group
* @return array
*/
public static function map($array, $from, $to, $group = null)
{
$result = [];
foreach ($array as $element) {
$key = static:: getValue($element, $from);
$value = static:: getValue($element, $to);
if ($group !== null) {
$result[ static:: getValue($element, $group)][$key] = $value;
} else {
$result[$key] = $value;
}
}
return $result;
}The above is the content of Yii2.0 ArrayHelper::map() usage. For more related content, please pay attention to the PHP Chinese website (www.php.cn)!
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