获取数组的第一个元素

Question

I have an array:

array( 4 => 'apple', 7 => 'orange', 13 => 'plum' )

I would like to get the first element of this array. Expected result: string apple

One requirement: it cannot be done with passing by reference, so array_shift is not a good solution.

How can I do this?

转载于:https://stackoverflow.com/questions/1921421/get-the-first-element-of-an-array

Answer 1

Original answer, but costly (O(n)):

array_shift(array_values($array));

In O(1):

array_pop(array_reverse($array));

Edited with suggestions from comments for other use cases etc...

If modifying (in the sense of resetting array pointers) of $array is not a problem, you might use:

reset($array);

This should be theoretically more efficient, if a array "copy" is needed:

array_shift(array_slice($array, 0, 1)); 

With PHP 5.4+ (but might cause an index error if empty):

array_values($array)[0];