php array merge not giving expected/desired results - php

Question

With the following code I am able to generate 2 arrays..
function readCSV($csvFile){
$file_handle = fopen($csvFile, 'r');
//ignores first line of csv
fgetcsv($file_handle);
while (!feof($file_handle) ) {
$line_of_text[] = fgetcsv($file_handle, 1024);
}
fclose($file_handle);
return $line_of_text;
}
// Set path to CSV file
$csvFile = 'csv1.csv';
$csvFile2 = 'csv2.csv';
$csv = readCSV($csvFile);
$csv2 = readCSV($csvFile2);
echo '<pre>';
$arr = [];
//$csv is your array
foreach($csv as $key => $value){
if(!array_key_exists($value[24],$arr)){
$arr[$value[24]] = [];
}
$arr[$value[24]] = array_merge($arr[$value[24]],$value);
}
//ignores last item in array
array_pop($arr);
$arr2 = [];
//$csv2 is your array
foreach($csv2 as $key => $value){
if(!array_key_exists($value[1],$arr2)){
$arr2[$value[1]] = [];
}
$arr2[$value[1]] = array_merge($arr2[$value[1]],$value);
}
echo '<pre>';
print_r($arr);
print_r($arr2);
echo '</pre>';
This outputs the arrays as follows..
Array 1 ($arr)
Array
(
[1593608448] => Array
(
[0] => 03/25/20
[1] => Vinyl Decal Sticker
[2] =>
[3] => 1
[4] => 2.85
[5] =>
[6] =>
[7] => 0.00
[8] => 0.00
[9] => 2.49
[10] => 0
[11] => 2.85
[12] => GBP
[13] => 1829006957
[14] => 627718667
[15] => 03/25/2020
[16] => 03/25/2020
[17] => John Smith
[18] => Any Street
[19] =>
[20] => Somewhere
[21] => Someplace
[22] => PC0 DE
[23] => United Kingdom
[24] => 1593608448
[25] => Colour:Yellow
[26] => online
[27] => listing
[28] => online_cc
[29] =>
[30] =>
[31] => 0
)
)
And array 2 ($arr2)
Array
(
[1593608448] => Array
(
[0] => 03/25/20
[1] => 1593608448
[2] =>
[3] => John Smith
[4] => John
[5] => Smith
[6] => 1
[7] => Credit Card
[8] => 03/25/20
[9] => Any Street
[10] =>
[11] => Somewhere
[12] => Someplace
[13] => PC 0DE
[14] => United Kingdom
[15] => GBP
[16] => 2.85
[17] =>
[18] =>
[19] => 0.00
[20] => 0.00
[21] => 2.49
[22] => 0
[23] => 5.88
[24] =>
[25] => 0.44
[26] => 4.9
[27] =>
[28] =>
[29] =>
[30] => John Smith
[31] => online
[32] => online_cc
[33] =>
[34] =>
)
)
I have attempted to merge these arrays with..
$merged = array_merge($arr,$arr2);
print_r($merged);
This outputs as..
Array
(
[0] => Array
(
[0] => 03/25/20
[1] => Vinyl Decal Sticker
[2] =>
[3] => 1
[4] => 2.85
[5] =>
[6] =>
[7] => 0.00
[8] => 0.00
[9] => 2.49
[10] => 0
[11] => 2.85
[12] => GBP
[13] => 1829006957
[14] => 627718667
[15] => 03/25/2020
[16] => 03/25/2020
[17] => John Smith
[18] => Any Street
[19] =>
[20] => Somewhere
[21] => Someplace
[22] => PC0 DE
[23] => United Kingdom
[24] => 1593608448
[25] => Colour:Yellow
[26] => online
[27] => listing
[28] => online_cc
[29] =>
[30] =>
[31] => 0
)
[1] => Array
(
[0] => 03/25/20
[1] => 1593608448
[2] =>
[3] => John Smith
[4] => John
[5] => Smith
[6] => 1
[7] => Credit Card
[8] => 03/25/20
[9] => Any Street
[10] =>
[11] => Somewhere
[12] => Someplace
[13] => PC 0DE
[14] => United Kingdom
[15] => GBP
[16] => 2.85
[17] =>
[18] =>
[19] => 0.00
[20] => 0.00
[21] => 2.49
[22] => 0
[23] => 5.88
[24] =>
[25] => 0.44
[26] => 4.9
[27] =>
[28] =>
[29] =>
[30] => John Smith
[31] => online
[32] => online_cc
[33] =>
[34] =>
)
)
When I wanted/expected..
Array
(
[1593608448] => Array
(
[0] => 03/25/20
[1] => Vinyl Decal Sticker
[2] =>
[3] => 1
[4] => 2.85
[5] =>
[6] =>
[7] => 0.00
[8] => 0.00
[9] => 2.49
[10] => 0
[11] => 2.85
[12] => GBP
[13] => 1829006957
[14] => 627718667
[15] => 03/25/2020
[16] => 03/25/2020
[17] => John Smith
[18] => Any Street
[19] =>
[20] => Somewhere
[21] => Someplace
[22] => PC0 DE
[23] => United Kingdom
[24] => 1593608448
[25] => Colour:Yellow
[26] => online
[27] => listing
[28] => online_cc
[29] =>
[30] =>
[31] => 0
[32] => 03/25/20
[33] => 1593608448
[34] =>
[35] => John Smith
[36] => John
[37] => Smith
[38] => 1
[39] => Credit Card
[40] => 03/25/20
[41] => Any Street
[42] =>
[43] => Somewhere
[44] => Someplace
[45] => PC 0DE
[46] => United Kingdom
[47] => GBP
[48] => 2.85
[49] =>
[50] =>
[51] => 0.00
[52] => 0.00
[53] => 2.49
[54] => 0
[55] => 5.88
[56] =>
[57] => 0.44
[58] => 4.9
[59] =>
[60] =>
[61] =>
[62] => John Smith
[63] => online
[64] => online_cc
[65] =>
[66] =>
)
)
So keeping the order id (which is always [24] in 1 arr1 and [2] in the arr2) as the key then add on to the end of the matching key in $arr1 the contents of the matching key from $arr2 with the numbers just following on.
I have looked at many similar questions and answers on here but not getting the results I require.
Or another way of putting it is it will check if [24] and [2] match and then append on to the end

Answer 1

It would be better to merge the data as you read it. I was going to change your read so that it read the CSV as it created the arrays, but I have left the readCSV() as it is - except to add array_filter() to remove empty elements.
Rather than create the two arrays and then merge them, I've change the second CSV loop to check $arr and add the data at this point...
function readCSV($csvFile){
$file_handle = fopen($csvFile, 'r');
//ignores first line of csv
fgetcsv($file_handle);
while (!feof($file_handle) ) {
$line_of_text[] = fgetcsv($file_handle, 1024);
}
fclose($file_handle);
$line_of_text = array_filter($line_of_text);
return $line_of_text;
}
$csvFile = 'csv1.csv';
$csvFile2 = 'csv2.csv';
$csv = readCSV($csvFile);
$csv2 = readCSV($csvFile2);
echo '<pre>';
$arr = [];
//$csv is your array
foreach($csv as $key => $value){
if(!array_key_exists($value[24],$arr)){
$arr[$value[24]] = [];
}
$arr[$value[24]] = array_merge($arr[$value[24]],$value);
}
foreach($csv2 as $key => $value){
if(!array_key_exists($value[1],$arr)){
$arr[$value[1]] = [];
}
$arr[$value[1]] = array_merge($arr[$value[1]],$value);
}
echo '<pre>';
print_r($arr);
echo '</pre>';

Answer 2

Use array_merge_recursive instead of array_merge
$merged = array_merge_recursive($arr,$arr2);