Array_multisort for PHP Functions

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• Syntax

Add a two-dimensional array ($ sortarray) and sort it. What should we do?
PHP has already completed such a useful function for us: array_multisort

Field1	Field2	Field3	Field4	Field5	Field6	Fieldsort	Field8	Field9
1	***	***	***	***	***	3.025	***	***
2	***	***	***	***	***	6.756	***	***
3	***	***	***	***	***	5.375	***	***
4	***	***	***	***	***	12.645	***	***
5	***	***	***	***	***	-6.548	***	***

We need to sort fieldsort in the order of size to small. Then we can first retrieve all values of the fieldsort field and name it $ fieldinarray;

Use the array_multisort function for sorting. The reference code is as follows:

//get fileds in arrayforeach($tempArray as $row)        $fieldInArray[] =  $row['FIELDSORT'];.........................................//sort tempArrayarray_multisort($fieldInArray,SORT_STRING,SORT_DESC,$tempArray);

In this way, the fieldsort of $ temparray will be sorted in the ascending order.

Definition and usage

The array_multisort () function sorts multiple arrays or multi-dimensional arrays.

The array in the parameter is treated as a table column and sorted by rows-this is similar to the SQL order by statement.
Clause. The first array is the main array to be sorted. If the rows (values) in the array are the same, they are sorted according to the corresponding values in the next input array.

The first parameter is an array, and each subsequent parameter may be an array or one of the following sort order signs (the sort mark is used to change the default sort order:

• Sort_asc-default, in ascending order. A-Z)
• Sort_desc-sort in descending order. Z-A)

You can then specify the sorting type:

• Sort_regular-default. Sort each item in the general order.
• Sort_numeric-Sort each item in numerical order.
• Sort_string-Sort each item in alphabetical order.

Syntax

array_multisort(array1,sorting order,sorting type,array2,array3...)

Parameters	Description
Array1	Required. Specifies the input array.
Sorting order	Optional. Specify the order. Possible values are sort_asc and sort_desc.
Sorting type	Optional. Specifies the sorting type. Possible values are sort_regular, sort_numeric, and sort_string.
Array2	Optional. Specifies the input array.
Array3	Optional. Specifies the input array.

Tips and comments

Note: The string key will be retained, but the number key will be re-indexed, starting from 0 and increasing at 1.

Note: You can set the sorting order and type behind each array. If no value is set, the default value is used for each array parameter.

Example 1

<?php
$a1=array("Dog","Cat");
$a2=array("Fido","Missy");
array_multisort($a1,$a2);
print_r($a1);
print_r($a2);
?>

Output:

Array ( [0] => Cat [1] => Dog )
Array ( [0] => Missy [1] => Fido )

Example 2

How to sort two values at the same time:

<?php
$a1=array("Dog","Dog","Cat");
$a2=array("Pluto","Fido","Missy");
array_multisort($a1,$a2);
print_r($a1);
print_r($a2);
?>

Output:

Array ( [0] => Cat [1] => Dog [2] => Dog )
Array ( [0] => Missy [1] => Fido [2] => Pluto )

Example 3

With sorting parameters:

<?php
$a1=array("Dog","Dog","Cat");
$a2=array("Pluto","Fido","Missy");
array_multisort($a1,SORT_ASC,$a2,SORT_DESC);
print_r($a1);
print_r($a2);
?>

Output:

Array ( [0] => Cat [1] => Dog [2] => Dog )
Array ( [0] => Missy [1] => Pluto [2] => Fido )