php搜索数组键并获取值

I was wondering what is the best way to search keys in an array and return it's value. Something like array_search but for keys. Would a loop be the best way?

我想知道在数组中搜索键并返回其值的最佳方法是什么。类似于array_search但是用于键。循环是最好的方法吗？

Array:

阵：

Array([20120425] => 409 [20120426] => 610 [20120427] => 277
      [20120428] => 114 [20120429] => 32 [20120430] => 304
      [20120501] => 828 [20120502] => 803 [20120503] => 276 [20120504] => 162)

Value I am searching for : 20120504

我正在寻找的价值：20120504

4 个解决方案

#1

The key is already the ... ehm ... key

钥匙已经是......呃...钥匙

echo $array[20120504];

If you are unsure, if the key exists, test for it

如果您不确定，如果密钥存在，请测试它

$key = 20120504;
$result = isset($array[$key]) ? $array[$key] : null;

Minor addition:

次要补充：

$result = @$array[$key] ?: null;

One may argue, that @ is bad, but keep it serious: This is more readable and straight forward, isn't?

有人可能会争辩说，@是坏的，但要保持严肃：这更具可读性和直接性，不是吗？

Update: With PHP7 my previous example is possible without the error-silencer

更新：使用PHP7，我可以在没有错误消音器的情况下使用上一个示例

$result = $array[$key] ?? null;

#2

<?php

// Checks if key exists (doesn't care about it's value).
// @link http://php.net/manual/en/function.array-key-exists.php
if (array_key_exists(20120504, $search_array)) {
  echo $search_array[20120504];
}

// Checks against NULL
// @link http://php.net/manual/en/function.isset.php
if (isset($search_array[20120504])) {
  echo $search_array[20120504];
}

// No warning or error if key doesn't exist plus checks for emptiness.
// @link http://php.net/manual/en/function.empty.php
if (!empty($search_array[20120504])) {
  echo $search_array[20120504];
}

?>

#3

array_search('20120504', array_keys($your_array));

#4

-1

Here is an example straight from PHP.net

这是一个直接来自PHP.net的例子

$a = array(
    "one" => 1,
    "two" => 2,
    "three" => 3,
    "seventeen" => 17
);

foreach ($a as $k => $v) {
    echo "\$a[$k] => $v.\n";
}

in the foreach you can do a comparison of each key to something that you are looking for

在foreach中，您可以将每个键与您正在寻找的内容进行比较

#1