blocks|key|1102111|text|虽然end()似乎是最简单的，但它并不是最快的。更快、更强大的替代方案是array_slice()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1102112|$lastKey+=+key(array_slice($array,+-1,+1,+true));|code-block|syntax|javascript|1102113|As+the+tests+say，在一个有500000个元素的数组上，它几乎快了7倍！|1102114|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/array-slice|1|https://3v4l.org/17XLq^0|2|5|10|D|10|D|0|0|0|0|G|1|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@$9|11|A|12|1|13]]|E|$]]|$1|F|3|G|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|15|8|@]|D|@$9|16|A|17|1|18]]|E|$]]|$1|M|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|N|$O|$5|P|Q|R|E|$S|T]]|U|$5|P|Q|R|E|$S|V]]]]

Although <code>end()</code> seems to be the easiest, it's not the fastest. The faster, and much stronger alternative is <a href="http://php.net/array-slice" rel="noreferrer"><code>array_slice()</code></a>:

<pre><code>$lastKey = key(array_slice($array, -1, 1, true));
</code></pre>

<a href="https://3v4l.org/17XLq" rel="noreferrer">As the tests say</a>, on an array with 500000 elements, it is almost 7x faster!

blocks|key|1102150|text|我更喜欢|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102151|end(array_keys($myarr))|code-block|syntax|javascript|1102152|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I prefer 

<pre><code>end(array_keys($myarr))
</code></pre>

blocks|key|1317148|text|只需使用：echo+$array[count($array)+-+1];|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1317149|entityMap^0|5|V|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

Just use : <code>echo $array[count($array) - 1];</code>

blocks|key|1102263|text|我不知道这是否会更快，但这样做似乎更容易，而且您可以通过不向end()传递函数来避免错误……|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102264|它只需要一个变量。多写一行代码，然后在需要时取消设置，这不是什么大问题。|1102265|$array+=+array(
++++'first'+=>+123,
++++'second'+=>+456,
++++'last'+=>+789,+
);

$keys+=+array_keys($array);
$last+=+end($keys);|code-block|syntax|javascript|1102266|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Dont know if this is going to be faster or not, but it seems easier to do it this way, and you avoid the error by not passing in a function to end()... 

it just needed a variable... not a big deal to write one more line of code, then unset it if you needed to.

<pre><code>$array = array(
 'first' =&gt; 123,
 'second' =&gt; 456,
 'last' =&gt; 789, 
);

$keys = array_keys($array);
$last = end($keys);
</code></pre>

blocks|key|1102539|text|从PHPPHP7.3开始，array_key_last()是获取任何数组的最后一个键的最佳方法。仅仅为了获取数组的最后一个键而组合使用end()、key()和reset()是令人震惊的。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1102540|$array+=+array("one"+=>+bird,+"two"+=>+"fish",+3+=>+"elephant");
$key+=+array_key_last($array);
var_dump($key)+//output+3|code-block|syntax|javascript|1102541|将其与|1102542|end($array)
$key+=+key($array)
var_dump($key)+//output+3
reset($array)|1102543|如果组合使用end()和key()，则必须将指针重置为位于开头的数组|1102544|entityMap^0|D|G|1V|5|21|5|27|7|0|0|0|0|6|5|C|5|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|11|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|12|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|13|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|14|8|@$9|15|A|16|B|C]|$9|17|A|18|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|R|$]]

As of PHP >= 7.3 <code>array_key_last()</code> is the best way to get the last key of any of an array. Using combination of <code>end()</code>, <code>key()</code> and <code>reset()</code> just to get last key of an array is outrageous.

<pre><code>$array = array("one" =&gt; bird, "two" =&gt; "fish", 3 =&gt; "elephant");
$key = array_key_last($array);
var_dump($key) //output 3
</code></pre>

compare that to

<pre><code>end($array)
$key = key($array)
var_dump($key) //output 3
reset($array)
</code></pre>

You must reset array for the pointer to be at the beginning if you are using combination of <code>end()</code> and <code>key()</code>

blocks|key|1317043|text|尝试使用array_pop和array_keys函数，如下所示：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1317044|<?php

$array+=+array(
++++'one'+=>+1,
++++'two'+=>+2,
++++'three'+=>+3
);

echo+array_pop(array_keys($array));+//+prints+three

?>|code-block|syntax|javascript|1317045|entityMap|0|LINK|mutability|MUTABLE|url|http://php.net/manual/en/function.array-pop.php|1|http://php.net/manual/en/function.array-keys.php^0|4|9|0|E|A|1|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]|$A|W|B|X|1|Y]]|C|$]]|$1|D|3|E|5|F|7|Z|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|10|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]|Q|$5|L|M|N|C|$O|R]]]]

Try using <a href="http://php.net/manual/en/function.array-pop.php" rel="noreferrer">array_pop</a> and <a href="http://php.net/manual/en/function.array-keys.php" rel="noreferrer">array_keys</a> function as follows:

<pre><code>&lt;?php

$array = array(
 'one' =&gt; 1,
 'two' =&gt; 2,
 'three' =&gt; 3
);

echo array_pop(array_keys($array)); // prints three

?&gt;
</code></pre>

blocks|key|1102375|text|您可以使用以下命令：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102376|$array+=+array("one"+=>+"apple",+"two"+=>+"orange",+"three"+=>+"pear");
end($array);+
echo+key($array);|code-block|syntax|javascript|1102377|另一个解决方案是创建一个函数并使用它：|1102378|function+endKey($array){
end($array);
return+key($array);
}

$array+=+array("one"+=>+"apple",+"two"+=>+"orange",+"three"+=>+"pear");
echo+endKey($array);|1102379|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

You can use this:

<pre><code>$array = array("one" =&gt; "apple", "two" =&gt; "orange", "three" =&gt; "pear");
end($array); 
echo key($array);
</code></pre>

Another Solution is to create a function and use it:

<pre><code>function endKey($array){
end($array);
return key($array);
}

$array = array("one" =&gt; "apple", "two" =&gt; "orange", "three" =&gt; "pear");
echo endKey($array);
</code></pre>

blocks|key|1317552|text|这很奇怪，但为什么这个话题没有这样的答案：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317553|$lastKey+=+array_keys($array)[count($array)-1];|offset|length|style|CODE|1317554|entityMap^0|0|0|1B|0^^$0|@$1|2|3|4|5|6|7|J|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|K|8|@$D|L|E|M|F|G]]|9|@]|A|$]]|$1|H|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|I|$]]

It is strange, but why this topic is not have this answer: 

<code>$lastKey = array_keys($array)[count($array)-1];</code>

blocks|key|1102270|text|$arr+=+array('key1'=>'value1','key2'=>'value2','key3'=>'value3');
list($last_key)+=+each(array_reverse($arr));
print+$last_key;
//+key3|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1102271|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>$arr = array('key1'=&gt;'value1','key2'=&gt;'value2','key3'=&gt;'value3');
list($last_key) = each(array_reverse($arr));
print $last_key;
// key3
</code></pre>

blocks|key|1317368|text|我只是从Xander获取了helper-function，并使用前面的答案对其进行了改进：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317369|function+last($array){
++$keys+=+array_keys($array);
++return+end($keys);
}


$arr+=+array("one"+=>+"apple",+"two"+=>+"orange",+"three"+=>+"pear");++++
echo+last($arr);
echo+$arr(last($arr));|code-block|syntax|javascript|1317370|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I just took the helper-function from Xander and improved it with the answers before:

<pre><code>function last($array){
 $keys = array_keys($array);
 return end($keys);
}


$arr = array("one" =&gt; "apple", "two" =&gt; "orange", "three" =&gt; "pear"); 
echo last($arr);
echo $arr(last($arr));
</code></pre>

blocks|key|1317680|text|如果Array为array，则最后一个键为|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317681|last_key+=+array[array.length-1]|code-block|syntax|javascript|1317682|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If the Array is array,
then the last key is
<pre><code>last_key = array[array.length-1]
</code></pre>

blocks|key|1102486|text|用array_reverse()试试这个。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1102487|+$arr+=+array(
+++++'first'+=>+01,
+++++'second'+=>+10,
+++++'third'+=>+20,+
+);++
+$key+=+key(array_reverse($arr));
+var_dump($key);|code-block|syntax|javascript|1102488|entityMap^0|1|F|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

Try this one with <code>array_reverse()</code>. 

<pre><code> $arr = array(
 'first' =&gt; 01,
 'second' =&gt; 10,
 'third' =&gt; 20, 
 ); 
 $key = key(array_reverse($arr));
 var_dump($key);
</code></pre>

blocks|key|1102618|text|或在php+>=+7.3.0中|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1102619|您可以使用函数array_key_last()|1102620|如php.net中所述-获取数组的最后一个键|1102621|https://www.php.net/manual/en/function.array-key-last.php|1102622|entityMap|0|LINK|mutability|MUTABLE|url^0|2|C|0|7|G|0|0|0|1L|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|V|8|@$9|W|A|X|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|Y|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|Z|8|@]|D|@$9|10|A|11|1|12]]|E|$]]|$1|L|3|-4|5|6|7|13|8|@]|D|@]|E|$]]]|M|$N|$5|O|P|Q|E|$R|K]]]]

Or in <code>php &gt;= 7.3.0</code>
you can use the function <code>array_key_last()</code>
As described in php.net — Gets the last key of an array
<a href="https://www.php.net/manual/en/function.array-key-last.php" rel="nofollow noreferrer">https://www.php.net/manual/en/function.array-key-last.php</a>

blocks|key|1102330|text|$array+=+array(
++++'something'+=>+array(1,2,3),
++++'somethingelse'+=>+array(1,2,3,4)
);

$last_value+=+end($array);
$last_key+=+key($array);+//+'somethingelse'|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1102331|这之所以有效，是因为PHP在内部为$array移动了数组指针。|unstyled|1102332|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|J|8|@]|9|@]|A|$]]|$1|G|3|-4|5|F|7|K|8|@]|9|@]|A|$]]]|H|$]]

<pre><code>$array = array(
 'something' =&gt; array(1,2,3),
 'somethingelse' =&gt; array(1,2,3,4)
);

$last_value = end($array);
$last_key = key($array); // 'somethingelse'
</code></pre>

This works because PHP moves it's array pointer internally for $array

blocks|key|1317404|text|也可以使用内联使用的最佳可能解决方案：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1317405|end($arr)+&&+false+?:+key($arr)|code-block|syntax|javascript|1317406|这种解决方案只是表达式/语句，并提供了良好的性能并不是最好的可能。|1317407|内联示例用法：|1317408|$obj->setValue(
++++end($arr)+&&+false+?:+key($arr)+//+last+$arr+key
);|1317409|更新:在PHP+7.3%2B中:使用(当然)新添加的array_key_last()方法。|offset|length|style|CODE|1317410|entityMap^0|0|0|0|0|0|O|G|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|W|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|D|7|Y|8|@]|9|@]|A|$E|F]]|$1|M|3|N|5|6|7|Z|8|@$O|10|P|11|Q|R]]|9|@]|A|$]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

The best possible solution that can be also used used inline:

<pre><code>end($arr) &amp;&amp; false ?: key($arr)
</code></pre>

This solution is only expression/statement and provides good is not the best possible performance.

Inlined example usage:

<pre><code>$obj-&gt;setValue(
 end($arr) &amp;&amp; false ?: key($arr) // last $arr key
);
</code></pre>

 
UPDATE: In PHP 7.3+: use (of course) the newly added <code>array_key_last()</code> method.

blocks|key|1102676|text|尝试执行以下操作以保持与旧版本PHP的兼容性：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1102677|$array_keys++++=+array_keys(+$array+);
$last_item_key+=+array_pop(+$array_keys+);|code-block|syntax|javascript|1102678|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Try this to preserve compatibility with older versions of PHP:
<pre><code>$array_keys = array_keys( $array );
$last_item_key = array_pop( $array_keys );
</code></pre>

How can I get the last key of an array?

问如何获取数组中的最后一个键？
EN

回答 16

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问如何获取数组中的最后一个键？EN

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问如何获取数组中的最后一个键？
EN