How to get last key in an array?

我怎样才能得到数组的最后一个键？

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A solution would be to use a combination of end and key (quoting) :

end() advances array 's internal pointer to the last element, and returns its value.

key() returns the index element of the current array position.

So, a portion of code such as this one should do the trick :

$array = array(
    'first' => 123,
    'second' => 456,
    'last' => 789, 
);

end($array);         // move the internal pointer to the end of the array
$key = key($array);  // fetches the key of the element pointed to by the internal pointer

var_dump($key);

Will output :

string 'last' (length=4)

ie the key of the last element of my array.

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Although end() seems to be the easiest, it's not the fastest.

The faster, and much stronger alternative is array_slice()

Strike-out by editor: This claim has not been substantiated and contrary evidence has been mentioned in the comments. If there is any shred of truth to this poster's assertions about speed/efficiency then a benchmark test must be provided.

$last_key = key( array_slice( $array, -1, 1, TRUE ) );

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我更喜欢

end(array_keys($myarr))

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