array_multisort这个函数还是很有用的。
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array_multisort
(PHP 4, PHP 5, PHP 7)
array_multisort — Sort multiple or multi-dimensional arrays
Description
&$array1 [, mixed $array1_sort_order = SORT_ASC [, mixed$array1_sort_flags = SORT_REGULAR [, mixed $... ]]] )array_multisort() can be used to sort several arrays at once, or a multi-dimensional array by one or more dimensions.
Associative (string) keys will be maintained, but numeric keys will be re-indexed.
Note:网址:yii666.com
If two members compare as equal, their relative order in the sorted array is undefined.
Parameters
array1-
An array being sorted.
array1_sort_order-
The order used to sort the previous array argument. Either
SORT_ASCto sort ascendingly orSORT_DESCto sort descendingly.This argument can be swapped with
array1_sort_flagsor omitted entirely, in which caseSORT_ASCis assumed.文章来源地址:https://www.yii666.com/article/764266.html array1_sort_flags-
Sort options for the previous array argument:
Sorting type flags:
-
SORT_REGULAR- compare items normally (don't change types) -
SORT_NUMERIC- compare items numerically -
SORT_STRING- compare items as strings -
SORT_LOCALE_STRING- compare items as strings, based on the current locale. It uses the locale, which can be changed using setlocale() -
SORT_NATURAL- compare items as strings using "natural ordering" like natsort() -
SORT_FLAG_CASE- can be combined (bitwise OR) withSORT_STRINGorSORT_NATURALto sort strings case-insensitively
This argument can be swapped with
array1_sort_orderor omitted entirely, in which caseSORT_REGULARis assumed. -
...-
More arrays, optionally followed by sort order and flags. Only elements corresponding to equivalent elements in previous arrays are compared. In other words, the sort is lexicographical.
Return Values
Returns TRUE on success or FALSE on failure.
Changelog
| Version | Description |
|---|---|
| 5.4.0 | The SORT_NATURAL and SORT_FLAG_CASE were added to array1_sort_flags as possible sort flags. |
| 5.3.0 | The SORT_LOCALE_STRING was added to array1_sort_flags as possible sort flags. |
Examples
Example #1 Sorting multiple arrays
<?php
$ar1 = array(10, 100, 100, 0);
$ar2 = array(1, 3, 2, 4);
array_multisort($ar1, $ar2);
var_dump($ar1);
var_dump($ar2);
?>
In this example, after sorting, the first array will contain 0, 10, 100, 100. The second array will contain 4, 1, 2, 3. The entries in the second array corresponding to the identical entries in the first array (100 and 100) were sorted as well.
array(4) {
[0]=> int(0)
[1]=> int(10)
[2]=> int(100)
[3]=> int(100)
}
array(4) {
[0]=> int(4)
[1]=> int(1)
[2]=> int(2)
[3]=> int(3)
}
Example #2 Sorting multi-dimensional array
<?php
$ar = array(
array("10", 11, 100, 100, "a"),
array( 1, 2, "2", 3, 1)
);
array_multisort($ar[0], SORT_ASC, SORT_STRING,
$ar[1], SORT_NUMERIC, SORT_DESC);
var_dump($ar);
?>In this example, after sorting, the first array will transform to "10", 100, 100, 11, "a" (it was sorted as strings in ascending order). The second will contain 1, 3, "2", 2, 1 (sorted as numbers, in descending order).文章地址https://www.yii666.com/article/764266.html
array(2) {
[0]=> array(5) {
[0]=> string(2) "10"
[1]=> int(100)
[2]=> int(100)
[3]=> int(11)
[4]=> string(1) "a"
}
[1]=> array(5) {
[0]=> int(1)
[1]=> int(3)
[2]=> string(1) "2"
[3]=> int(2)
[4]=> int(1)
}
}
Example #3 Sorting database results
For this example, each element in the data array represents one row in a table. This type of dataset is typical of database records.
Example data:
volume | edition
-------+--------
67 | 2
86 | 1
85 | 6
98 | 2
86 | 6
67 | 7
The data as an array, called data. This would usually, for example, be obtained by looping with mysqli_fetch_assoc().
<?php
$data[] = array('volume' => 67, 'edition' => 2);
$data[] = array('volume' => 86, 'edition' => 1);
$data[] = array('volume' => 85, 'edition' => 6);
$data[] = array('volume' => 98, 'edition' => 2);
$data[] = array('volume' => 86, 'edition' => 6);
$data[] = array('volume' => 67, 'edition' => 7);
?>In this example, we will order by volume descending, edition ascending.
We have an array of rows, but array_multisort() requires an array of columns, so we use the below code to obtain the columns, then perform the sorting.
<?php
// Obtain a list of columns
foreach ($data as $key => $row) {
$volume[$key] = $row['volume'];
$edition[$key] = $row['edition'];
}
// as of PHP 5.5.0 you can use array_column() instead of the above code
$volume = array_column($data, 'volume');
$edition = array_column($data, 'edition');
// Sort the data with volume descending, edition ascending
// Add $data as the last parameter, to sort by the common key
array_multisort($volume, SORT_DESC, $edition, SORT_ASC, $data);
?>
The dataset is now sorted, and will look like this:
volume | edition
-------+--------
98 | 2
86 | 1
86 | 6
85 | 6
67 | 2
67 | 7