How to stop loop string inside PHP loop with array - php

Question

I'm trying to stop $implode_demographics inside for loop below.
For example, if I use echo $implode_demographics inside loop, then I will get:
a01a01,a02a01,a02,a03a01,a02,a03,a04a01,a02,a03,a04,a05a01,a02,a03,a04,a05,a06a01,a02,a03,a04,a05,a06,a07a01,a02,a03,a04,a05,a06,a07,a08a01,a02,a03,a04,a05,a06,a07,a08,a09a01,a02,a03,a04,a05,a06,a07,a08,a09,a10a01,a02,a03,a04,a05,a06,a07,a08,a09,a10,a11a01,a02,a03,a04,a05,a06,a07,a08,a09,a10,a11,b01a01,a02,a03,a04,a05,a06,a07,a08,a09,a10,a11,b01,b02a01,a02,a....
But If I use this string outside, then output works.
a01,a02,a03,a04,a05,a06,a07,a08,a09,a10,a11,b01,b02,b03,c01,c02,c03,c04,c05,c06,c07,c08,c09,c10,c11,c12,c13
Online PHP test
So, how I can echo $implode_demographics inside for loop to get same result?
$a_l_demographics = [11,3,13];
$a_p_demographics = ['a','b','c'];
$a_r_demographics = [];
$c_demographics_values = array();
$a_c_demographics = min(count($a_l_demographics), count($a_p_demographics));
for ($i = 0; $i < $a_c_demographics; $i++) {
for ($j = 1; $j <= $a_l_demographics[$i]; $j++) {
$a_r_demographics[] = $a_p_demographics[$i] . str_pad($j, 2, 0, STR_PAD_LEFT);
$implode_demographics = implode($a_r_demographics, ',');
// this won't work
echo $implode_demographics;
}
}
// this works
// echo $implode_demographics;

Answer 1

It doesn't works because you implode the same array again and again after you add data in it.
So in your first echo you have only a01, then you implode after with a01 and a02 value, etc.
Try to add echo $implode_demographics . "\n"; and you will see that you have one var, then two, then three, etc. see example here : https://3v4l.org/WrCgJ
So if you want to echo each value INSIDE, just do :
<?php
$a_l_demographics = [11,3,13];
$a_p_demographics = ['a','b','c'];
$a_r_demographics = [];
$c_demographics_values = array();
$a_c_demographics = min(count($a_l_demographics), count($a_p_demographics));
for ($i = 0; $i < $a_c_demographics; $i++) {
for ($j = 1; $j <= $a_l_demographics[$i]; $j++) {
$a_r_demographics[] = $a_p_demographics[$i] . str_pad($j, 2, 0, STR_PAD_LEFT);
$implode_demographics = implode($a_r_demographics, ',');
// You echo only the last value
echo $a_p_demographics[$i] . str_pad($j, 2, 0, STR_PAD_LEFT);
// If it's not the last loop : you add a `,`
if (!($i == ($a_c_demographics - 1) && $j == $a_l_demographics[$i]))
echo ",";
}
}
This way you will echo only the LAST value each time and not all the value from the beginning each time, the output is :
a01,a02,a03,a04,a05,a06,a07,a08,a09,a10,a11,b01,b02,b03,c01,c02,c03,c04,c05,c06,c07,c08,c09,c10,c11,c12,c13
See code here : https://3v4l.org/MEnGe

Answer 2

In fact it's work, you have a problem with the implode. Implode d'ont put the glue (,) to the last value !
try this.
$implode_demographics = implode($a_r_demographics, ',');
echo $implode_demographics.', ';