配列関数・2回目

はじめに

配列関数を整理する。2回目。

array_search

特定の値を検索する

array_search.php

$data = ['PHP', 'Javascript', 'PHP', 'Java', 'C#', '15'];
$data2 = ['X' => 10, 'Y' => 20, 'Z' => 30];
var_dump(array_search('Javascript', $data); //int(1)
var_dump(array_search('PHP', $data); //int(0)
var_dump(array_search('Java', $data); //bool(false)
var_dump(array_search(15, $data); //int(5)
var_dump(array_search(15, $data, true); //bool(false)
var_dump(array_search(10, $data2); //string(1) "X"

in_array

要素の有無を判定する

in_array.php

$data = ['PHP', 'Javascript', 'PHP', 'Java', 'C#', '15'];
var_dump(in_array('PHP', $data); //true

sort

配列の内容を並べ替える

sort.php

$data = ['Tennis', 'Swimming', 'Soccer', 'Baseball'];
sort($data, SORT_STRING);
print_r($data); // ['Baseball', 'Swimming', 'Soccer', 'Tennis']
rsort($data, SORT_STRING);
print_r($data); // ['Tennis', 'Soccer', 'Swimming', 'Baseball']

$data2 = ['Tennis' => 1, 'Swimming' => 1, 'Soccer' => 11, 'Baseball' => 9];
sort($data2, SORT_NUMERIC);
print_r($data2); // [1, 1, 9, 11]

$data3 = ['Tennis' => 1, 'Swimming' => 1, 'Soccer' => 11, 'Baseball' => 9];
asort($data3, SORT_NUMERIC);
print_r($data3); // [[Tennis] => 1 [Swimming] => 1 [Baseball] => 9 [Soccer] => 11]
ksort($data3, SORT_STRING);
print_r($data3); // [[Baseball] => 9 [Soccer] => 11 [Swimming] => 1 [Tennis] => 1]