Tác dụng của hàm ksort()
The ksort() function sorts an associative array in ascending order, according to the key.
The keys are preserved, i.e. the key-to-value mapping will remain unchanged by the sort operation.
The following table summarizes the technical details of this function.
| Return Value: | Returns TRUE on success or FALSE on failure. |
|---|---|
| Version: | PHP 4+ |
Syntax
The basic syntax of the ksort() function is given with:
The following example shows the ksort() function in action.
Example
Run this code »<?php
// Sample array
$alphabets = array("b"=>"ball", "d"=>"dog", "a"=>"apple", "c"=>"cat");
// Sorting alphabets array
ksort($alphabets);
print_r($alphabets);
?>Tip: The ksort() and krsort() functions used for sorting associative arrays by key, whereas the asort() and arsort() functions mainly used for sorting associative arrays by value.
Parameters
The ksort() function accepts the following parameters.
| Parameter | Description |
|---|---|
| array | Required. Specifies the array to sort. |
| sort_flags |
Optional. Specifies how array items should be compared. Possible values are:
|
More Examples
Here're some more examples showing how ksort() function actually works:
The following example sorts the "persons" associative array by key in ascending order:
Example
Run this code »<?php
// Sample array
$persons = array("Harry"=>18, "Clark"=>32, "Peter"=>20, "John"=>24);
// Sorting persons array
ksort($persons);
print_r($persons);
?>