Question

我正在尝试使用array_flip以逗号分隔格式打印重复值

$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"blue");
$flip=array_flip($a);
print_r($flip);

我的输出是：

Array ( [red] => a [green] => b [blue] => d )

但我的预期输出是：

Array ( [red] => a [green] => b [blue] => c,d)

我如何获得该输出？

Answer 1

您需要将您的功能与array_flip一样使用

$array = array("a"=>"red","b"=>"green","c"=>"blue","d"=>"blue");

$res = array_flip($array);

foreach ($res as $k => $v)
    $res[$k] = implode(", ", array_keys($array, $k));
print_r($res);

输出

Array
(
    [red] => a
    [green] => b
    [blue] => c, d
)

Demo

Answer 2

array_flip不会提供您的预期输出。您可以编写自定义函数，而不是这样：

$a=array("a"=>"red","b"=>"green","c"=>"blue","d"=>"blue");
$flip = array_flip_custom($a);

print_r($flip);
function array_flip_custom($a){
    $flip = array();
    foreach($a as $index=>$key){
        if($flip[$key]){
            $flip[$key] .= ','.$index;
        } else {
            $flip[$key] = $index;
        }
    }
    return $flip;
}

会给出输出：

数组（[红色] =＆gt; a [绿色] =＆gt; b [蓝色] =＆gt; c，d）

array_flip以逗号分隔格式打印重复值

2 个答案: