按字母顺序对数组进行排序php

Question

正如标题所示，我想在 php 中按字母顺序对数组进行排序。

$arr = array(
    'k' => 'pig',
    'e' => 'dog'
)

会变成

$arr = array(
    'e' => 'dog',
    'k' => 'pig'
)

有什么想法吗？

编辑：这是我要排序的实际数组。

Array ( [0] => Newtown [1] => Montgomery [2] => Welshpool [6] => Llanfyllin [7] => Llansanffraid [8] => Llanymynech [9] => Oswestry [14] => Oswestry Town Service [15] => Aston Way [16] => College Road [17] => Shrewsbury [18] => Royal Shrewsbury Hospital [19] => Worthen [20] => Brockton [22] => Cefn Blodwell [23] => Treflach [24] => Trefonen [25] => Morda [26] => Marches School [28] => North Shropshire College [37] => Park Hall [38] => Gobowen [39] => St Martins [40] => Ifton Heath [42] => Guilsfield [43] => Four Crosses [45] => Pant [46] => Llynclys [49] => Oswestry Town Service Schools [51] => Woodside School [56] => Whittington [57] => Babbinswood [58] => Hindford [59] => Ellesmere [62] => Forden [63] => Kingswood Cock Hotel [65] => Coleg Powys [85] => Borfa Green [86] => Bryn Siriol [87] => Maesydre School [92] => Crew Green [93] => Ford [104] => Llanrhaeadr [106] => Meifod [114] => Llangynog [116] => Llangedwyn [119] => Porthywaen [132] => Llanfair Caereinion [133] => Pontrobet [136] => Dolanog [141] => Llansilin [144] => Abermule [145] => Llandyssil [146] => Carhowel [149] => Cefn Coch [150] => Tregynon [151] => Manafon [152] => Berriew [157] => Bettws Cedewain [158] => Newtown High School [160] => Newtown Coleg Powys [173] => Llanerfyl [174] => Machynlleth [175] => Talybont [176] => Aberystwyth [183] => Bala [184] => Llanrwst [185] => Llandudno [188] => Middletown [196] => Llanidloes [202] => Wrexham [203] => Rhayader )

Answer 1

你想要php函数“asort”：

http://php.net/manual/en/function.asort.php

它对数组进行排序，维护索引关联。

编辑：我刚刚注意到您使用的是标准数组（非关联）。如果您不关心保留索引关联，请使用 sort()：

http://php.net/manual/en/function.sort.php

Answer 2

• 如果您只想对数组值进行排序而不关心键，请使用sort()。这将提供一个新数组，其中包含从 0 开始的数字键。
• 如果要保留键值关联，请使用asort()。

另请参阅comparison table of sorting functions in PHP。

Answer 3

注意sort()对数组的操作就地，所以只需要调用

sort($a);
doSomething($a);

这行不通；

$a = sort($a);
doSomething($a);

Answer 4

asort() - 保持键关联：是。

sort() - 保持键关联：否。

来源：http://php.net/manual/en/array.sorting.php