我如何排序这个对象数组的一个字段，如名称或计数?
Array
(
[0] => stdClass Object
(
[ID] => 1
[name] => Mary Jane
[count] => 420
)
[1] => stdClass Object
(
[ID] => 2
[name] => Johnny
[count] => 234
)
[2] => stdClass Object
(
[ID] => 3
[name] => Kathy
[count] => 4354
)
....
当前回答
你可以使用Nspl中的排序函数:
use function \nspl\a\sorted;
use function \nspl\op\propertyGetter;
use function \nspl\op\methodCaller;
// Sort by property value
$sortedByCount = sorted($objects, propertyGetter('count'));
// Or sort by result of method call
$sortedByName = sorted($objects, methodCaller('getName'));
其他回答
如果你正在使用PHP oop，你可能需要更改为:
public static function cmp($a, $b)
{
return strcmp($a->name, $b->name);
}
//in this case FUNCTION_NAME would be cmp
usort($your_data, array('YOUR_CLASS_NAME','FUNCTION_NAME'));
这里所有答案的缺点是它们使用静态字段名，所以我写了一个OOP风格的调整版本。假设您正在使用getter方法，您可以直接使用这个类并使用字段名作为参数。也许有人会觉得它有用。
class CustomSort{
public $field = '';
public function cmp($a, $b)
{
/**
* field for order is in a class variable $field
* using getter function with naming convention getVariable() we set first letter to uppercase
* we use variable variable names - $a->{'varName'} would directly access a field
*/
return strcmp($a->{'get'.ucfirst($this->field)}(), $b->{'get'.ucfirst($this->field)}());
}
public function sortObjectArrayByField($array, $field)
{
$this->field = $field;
usort($array, array("Your\Namespace\CustomSort", "cmp"));;
return $array;
}
}
如果你想对日期排序
usort($threads,function($first,$second){
return strtotime($first->dateandtime) < strtotime($second->dateandtime);
});
用这个……
$array_list = [
"Apple" => 2,
"Pear" => 1,
"Orange" => 5,
"Lemon" => 1,
"Strawberry" => 2,
"Banana" => 3
];
function cmp($a, $b) {
return $b - $a;
}
$ao = new ArrayObject($object);
$ao->uasort('cmp');
print_r(json_encode($ao));
再见! !
Demodave对吃多键的参考答案
function array_sort_by(array $arr, $keys){
if(!is_array($keys))
$keyList = explode(',', $keys);
$keyList = array_keys(array_flip($keyList)); // array_unique
$keyList = array_reverse($keyList);
$result = &$arr;
foreach ($keyList as $key) {
if(array_key_exists($key, $arr))
$result = usort($result, function($a, $b) use ($key) { return strcmp($a->{$key}, $b->{$key}); });
}
return $result;
}
