超越PHP - Exceed PHP: arsort

说明

void arsort ( array array [, int sort_flags])

本函数对数组进行排序，数组的索引保持和单元的关联。主要用于对那些单元顺序很重要的结合数组进行排序。

例子 1. arsort() 例子


<?php

$fruits = array ("d"=>"lemon", "a"=>"orange", "b"=>"banana", "c"=>"apple");

arsort ($fruits);

reset ($fruits);

while (list ($key, $val) = each ($fruits)) {

    echo "$key = $val\n";

}

?>

本例输出如下：

a = orange
d = lemon
b = banana
c = apple

fruits 被按照字母顺序逆向排序，并且单元的索引关系不变。

可以用可选的参数 sort_flags 改变排序的行为，详情见 sort()。

参见 asort()，rsort()，ksort() 和 sort()。

add a note User Contributed Notes
arsort

morgan at anomalyinc dot com
25-Nov-1999 11:30

If you need to sort a multi-demension array, for example, an array such as




$TeamInfo[$TeamID]["WinRecord"]


$TeamInfo[$TeamID]["LossRecord"]


$TeamInfo[$TeamID]["TieRecord"]


$TeamInfo[$TeamID]["GoalDiff"]

$TeamInfo[$TeamID]["TeamPoints"]




and you have say, 100 teams here, and want to sort by
"TeamPoints":



first, create your multi-dimensional
array. Now, create another, single dimension array populated with the
scores from the first array, and with indexes of corresponding team_id...
ie

$foo[25] = 14

$foo[47] = 42

or whatever.

Now, asort or
arsort the second array.

Since the array is now sorted by score or
wins/losses or whatever you put in it, the indices are all
hoopajooped.

If you just walk through the array, grabbing the index of
each entry, (look at the asort example. that for loop does just that) then
the index you get will point right back to one of the values of the
multi-dimensional array.

Not sure if that's clear, but mail me if it
isn't...

-mo

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