Array PHP sebenarnya adalah peta yang diurutkan, artinya semua nilai array memiliki kunci, dan item di dalam array mempertahankan urutan. Saat menggunakan array sebagai daftar sederhana seperti yang telah kita lihat di bab sebelumnya, penghitung berbasis nol digunakan untuk mengatur kunci. Setiap item yang ditambahkan ke array menambah indeks berikutnya sebesar 1
Contoh yang baik untuk menggunakan array dengan kunci adalah buku telepon. Katakanlah kita ingin menyimpan nomor telepon orang di kelas
$phone_numbers = [ "Alex" => "415-235-8573", "Jessica" => "415-492-4856", ]; print_r($phone_numbers); echo "Alex's phone number is " . $phone_numbers["Alex"] . "\n"; echo "Jessica's phone number is " . $phone_numbers["Jessica"] . "\n";Untuk menambahkan item ke array menggunakan kunci, kami menggunakan operator tanda kurung, seperti yang Anda harapkan
$phone_numbers = [ "Alex" => "415-235-8573", "Jessica" => "415-492-4856", ]; $phone_numbers["Michael"] = "415-955-3857"; print_r($phone_numbers); _Untuk memeriksa apakah kunci ada di dalam array, kita dapat menggunakan fungsi array_key_exists
$phone_numbers = [ "Alex" => "415-235-8573", "Jessica" => "415-492-4856", ]; if (array_key_exists("Alex", $phone_numbers)) { echo "Alex's phone number is " . $phone_numbers["Alex"] . "\n"; } else { echo "Alex's phone number is not in the phone book!"; } if (array_key_exists("Michael", $phone_numbers)) { echo "Michael's phone number is " . $phone_numbers["Michael"] . "\n"; } else { echo "Michael's phone number is not in the phone book!"; }Jika kita hanya ingin mengekstrak kunci dari array (nama), kita dapat menggunakan fungsi array_keys
$phone_numbers = [ "Alex" => "415-235-8573", "Jessica" => "415-492-4856", ]; print_r(array_keys($phone_numbers));Alternatifnya, untuk mendapatkan nilai array saja (nomor telepon), kita dapat menggunakan fungsi array_values
$phone_numbers = [ "Alex" => "415-235-8573", "Jessica" => "415-492-4856", ]; print_r(array_values($phone_numbers)); _Latihan
Tambahkan nomor ke buku telepon untuk Eric, dengan nomor 415-874-7659, baik dengan menambahkannya ke definisi larik, atau sebagai baris kode terpisah
Fungsi key() adalah fungsi bawaan dalam PHP yang digunakan untuk mengembalikan indeks elemen array tertentu yang sedang ditunjuk oleh penunjuk internal. Elemen saat ini mungkin elemen awal atau berikutnya yang bergantung pada posisi kursor. Secara default posisi kursor berada pada indeks nol i. e, pada elemen awal dari array yang diberikan
Sintaksis
key($array)Parameter. Fungsi ini menerima parameter tunggal $array. Ini adalah larik yang ingin kami temukan elemen saat ini yang ditunjukkan oleh penunjuk internal
Nilai Pengembalian. Ini mengembalikan indeks elemen saat ini dari array yang diberikan. Jika array input kosong maka fungsi key() akan mengembalikan NULL
Program di bawah ini mengilustrasikan fungsi key() di PHP
Program 1
<?php
// input array
$arr =arrayThe index of the current element of the array is: 0 0$arr3The index of the current element of the array is: 0 2$arr5The index of the current element of the array is: 0 2$arr7The index of the current element of the array is: 0 2$arr9________6______8
Array_keys() adalah fungsi bawaan dalam PHP dan digunakan untuk mengembalikan semua kunci dari dan larik atau subset dari kunci
Sintaksis
array array_keys($input_array, $search_value, $strict)Parameter. Fungsi mengambil tiga parameter yang satu wajib dan dua lainnya opsional
- $input_array (wajib). Mengacu pada array yang ingin kita operasikan
- $search_value (opsional). Mengacu pada nilai array yang ingin kita cari elemen kuncinya. Jika parameter ini diteruskan maka fungsi akan mengembalikan kunci yang sesuai dengan elemen ini hanya jika tidak maka akan mengembalikan semua kunci dari array
- $ketat (opsional). Menentukan apakah perbandingan ketat (===) harus digunakan selama pencarian. palsu adalah nilai default
Nilai Pengembalian. Fungsi mengembalikan larik yang berisi semua kunci atau subset kunci larik input tergantung pada parameter yang diteruskan
Contoh
Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 )Dalam program di bawah ini, kami telah mengirimkan larik asosiatif sederhana ke fungsi array_keys(), untuk mencetak semua kuncinya
<?php
// PHP function to illustrate the use of array_keys()
function get_Key($arrayInput : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 0
Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 1
Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 2Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 3 Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 4Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 5Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 6$arrayInput : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 8
Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 2Array ( [0] => one [1] => 2 [2] => three ) 0Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 6Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 3Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 8
Array ( [0] => one [1] => 2 [2] => three ) _4
$array Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 4Array ( [0] => one [1] => 2 [2] => three ) 8Input : $input_array = ("one" => "shyam", 2 => "rishav", "three" => "gaurav") Output : Array ( [0] => one [1] => 2 [2] => three ) Input : $input_array = ("one", "two", "three", "one", "four", "three", "one", "one") $search_value = "one" Output : Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 6Array ( [0] => 0 [1] => 3 [2] => 6 [3] => 7 ) 0 2function8 2____30_______7____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________G