Cfrgtkky

I have an array of strings

$cities = ['New York', 'Boston', 'Los Angeles', 'Cincinnati', 'Chicago', 'Houston', 'Philadelphia', 'Dallas', 'Seattle'];

I want to retrieve all the strings that starts with letter A, then B, then C, and so on for each alphabet letters.

What is the best way to do it avoing useless code repetitions?

You can create a temporary multidimensional array with first letter as index. Try -

$cities = ['New York', 'Boston', 'Los Angeles', 'Cincinnati', 'Chicago', 'Houston', 'Philadelphia', 'Dallas', 'Seattle'];



foreach($cities as $city) {

    $first = substr($city, 0, 1);

    $temp_cities[$first] = $city;

}



var_dump($temp_cities);

Output

array(8) {

  ["N"]=>

  array(1) {

    [0]=>

    string(8) "New York"

  }

  ["B"]=>

  array(1) {

    [0]=>

    string(6) "Boston"

  }

  ["L"]=>

  array(1) {

    [0]=>

    string(11) "Los Angeles"

  }

  ["C"]=>

  array(2) {

    [0]=>

    string(10) "Cincinnati"

    [1]=>

    string(7) "Chicago"

  }

  ["H"]=>

  array(1) {

    [0]=>

    string(7) "Houston"

  }

  ["P"]=>

  array(1) {

    [0]=>

    string(12) "Philadelphia"

  }

  ["D"]=>

  array(1) {

    [0]=>

    string(6) "Dallas"

  }

  ["S"]=>

  array(1) {

    [0]=>

    string(7) "Seattle"

  }

}

To find cities start with 'C' do - var_dump($temp_cities['C'])

Please try this

<?php



$cities = ['New York', 'Boston', 'Los Angeles', 'Cincinnati', 'Chicago', 'Houston', 'Philadelphia', 'Dallas', 'Seattle'];

$new_array = ;

$search_string = 'C'; // Letter to search

foreach ($cities as $city) {

    if (strpos($city, $search_string) === 0) {

        $new_array = $city;

    }

}

print_r($new_array);// New array will contian list of identified cities

?>

usort($cities, function($a, $b){

    return $a <=> $b;

});

If I understand correctly, you're trying to create 26 arrays, one for each letter of the alphabet, each array containing cities starting with that letter.

<?php

    $cities = ['New York', 'Boston', 'Los Angeles', 'Cincinnati', 'Chicago', 'Houston', 'Philadelphia', 'Dallas', 'Seattle'];



    //Our 26 arrays

    $arrA = array();

    $arrB = array();

    $arrC = array();

    $arrD = array();

    $arrE = array();

    $arrF = array();

    $arrG = array();

    $arrH = array();

    $arrI = array();

    $arrJ = array();

    $arrK = array();

    $arrL = array();

    $arrM = array();

    $arrN = array();

    $arrO = array();

    $arrP = array();

    $arrQ = array();

    $arrR = array();

    $arrS = array();

    $arrT = array();

    $arrU = array();

    $arrV = array();

    $arrW = array();

    $arrX = array();

    $arrY = array();

    $arrZ = array();



    //Fill the array for that city.

    foreach ($cities as $city){

        $key = substr($city, 0, 1);

        ${"arr".$key} = $city;

    }

    //Let's just test this worked.

    var_dump($arrC);

    var_dump($arrB);

    var_dump($arrN);



?>

You can simply sort array with

$cities = ['New York', 'Boston', 'Los Angeles', 'Cincinnati', 'Chicago', 'Houston', 'Philadelphia', 'Dallas', 'Seattle'];



sort($cities);