Php in_array() not working as expected [closed] - php

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I am currently working on a multiple select drop-down list. I need to display the selected values on an edit form.
in_array() is not working as I expect, do I have an error in my logic?
The code to display the selected values from the database is:
<div class="form-group">
<label class="col-md-3 control-label" for="selectbasic">Update Artist Selection</label>
<div class="col-md-6">
<select id="artists1" multiple="multiple" name="id_artist_fk[]" class="form-control ">
<?php
foreach ($artist_list as $key => $value) {
if (in_array($value['id_artist'], $current_artist_list, true)) {
$selected = "selected='selected'";
}
// print_r($value['id_artist']. "==". $current_artist_list);
echo "<option value=\"{$value['id_artist']}\" {$selected}>{$value['name']} {$value['surname']}</option>";
}
?>
</select>
</div>
</div>
The $artist_list is gotten via:
public function get_artist_list() {
$sql = "SELECT * FROM tbl_v_artist WHERE status != 0;";
$result = $this->database->doSelectQuery($sql);
$artists = array();
if ($result->num_rows > 0) {
while ($row = $result->fetch_array()) {
$artist = array(
'id_artist' => $row['id_artist'],
'name' => $row['name'],
'surname' => $row['surname'],
'status' => $row['status']
);
array_push($artists, $artist);
}
}
return $artists;
}
The $current_artist_list is gotten via:
$current_artist_list = $vid->get_artistsID_for_video($_POST['id_video']);
get_artistsID_for_video is:
public function get_artistsID_for_video($video_id) {
try {
$sql = "SELECT
tbl_video_artist.id_artist_fk
FROM tbl_video_artist
left join tbl_v_artist
ON tbl_v_artist.id_artist = tbl_video_artist.id_artists
WHERE tbl_video_artist.id_video_fk = {$video_id};";
//echo $sql;
$result = $this->database->doSelectQuery($sql);
$artists = array();
if ($result->num_rows > 0) {
while ($row = $result->fetch_array()) {
$artist = array(
'id_artist_fk' => $row['id_artist_fk']
);
array_push($artists, $artist);
}
}
return $artists;
} catch (Exception $ex) {
$ex->getMessage();
$ex->getFile();
}
}
Please help point me in the right direction.
I have edited the get_artistsID_for_video as follows:
public function get_artistsID_for_video($video_id) {
try {
$sql = "SELECT
tbl_video_artist.id_artist_fk
FROM tbl_video_artist
left join tbl_v_artist
ON tbl_v_artist.id_artist = tbl_video_artist.id_artists
WHERE tbl_video_artist.id_video_fk = {$video_id};";
//echo $sql;
$result = $this->database->doSelectQuery($sql);
// $artists = array();
if ($result->num_rows > 0) {
while ($row = $result->fetch_array()) {
$artist [] = $row['id_artist_fk'];
// array_push($artists, $artist);
}
return $artist;
}
} catch (Exception $ex) {
$ex->getMessage();
$ex->getFile();
}
}

Answer 1

Look at in_array manual:
in_array — Checks if a value exists in an array
So, what checks your in_array($value['id_artist'], $current_artist_list, true)?
It checks that in $current_artist_list exists value of $value['id_artist']. For example, if $value['id_artist'] is 20, in_array checks if value 20 is in your array.
But value 20 is NOT in your $current_artist_list array.
Because format of each element in your $current_artist_list is array('id_artist_fk' => $row['id_artist_fk']).
So, you're searching for 20, but value which you store is ('id_artist_fk' => 20).
20 NOT EQUALS array.
The fix is in get_artistsID_for_video():
while ($row = $result->fetch_array()) {
$artists[] = $row['id_artist_fk'];
}
Now you search for 20 in array where every element is a number too.
Making your search even faster (still in get_artistsID_for_video):
while ($row = $result->fetch_array()) {
// create array key with value of artist id
$artists[$row['id_artist_fk']] = 1;
}
And replace in_array with:
// check for existence of a key, not value.
if (!empty($current_artist_list[$value['id_artist']])) {
$selected = "selected='selected'";
}

Answer 2

Please check that $current_artist_list must be single array. i.e $current_artist_list[0] = 1;
$current_artist_list[1] = 2;
Which will match your id with condition. Right now it's looks like your $current_artist_list is associative array value having with key. Try to push only value as i mentioned above OR change the code as below.
$artists = array();
if ($result->num_rows > 0) {
while ($row = $result->fetch_array()) {
$artist = array(
'id_artist_fk' => $row['id_artist_fk']
);
array_push($artists, $row['id_artist_fk']);
}
}