Posting array to arrays in PHP - php

Question

I'm trying to post the implode data of multiple select html to database but it is dynamic.
Result will be like this:
data1|data2|data3 = from multiple select(already get)
how can I achieve this kind of result? It is separated with commas
data1|data2|data3, data1|data2|data3, data1|data2|data3
The separated data inside the commas come from another multiple select.
Here's my code
HTML
<div class="required field">
<label>Subjects:</label>
<select class="ui fluid search dropdown" name="pass_subj[]" multiple="">
<option value="">Subject</option>
<option value="data1">subject1</option>
<option value="data2">subject2</option>
<option value="data3">subject3</option>
<option value="data4">subject4</option>
<option value="data5">subject5</option>
</select>
</div>
<div class="two wide field" style="padding: 23px 0px 0px;">
<button class="passmore ui icon yellow button" type="button">
<i class="plus icon"></i>
</button>
</div>
php
$pass_subj = $_POST['pass_subj'];
$pass_subjs = implode("|", $pass_subj);

Answer 1

I solved my own problem: My current project was using fomantic-ui; on my previous attempt, I used multiple select via select tag, which gives combined array values. To fix this, I used a dropdown via a div tag:
<div class="required field">
<label>Subjects:</label>
<div class="ui multiple selection dropdown clearable">
<input name="pass_subj[]" type="hidden">
<i class="dropdown icon"></i>
<div class="default text">Subject</div>
<div class="menu">
<div class="item" data-value="AP">Araling Panlipunan</div>
<div class="item" data-value="ENG">English</div>
<div class="item" data-value="FIL">Filipino</div>
</div>
</div>
</div>
<div class="two wide field" style="padding: 23px 0px 0px;">
<button class="passmore ui icon yellow button" type="button"><i class="plus icon"></i></button>
</div>
My PHP:
$pass_subj = $_POST['pass_subj'];
$pass_subjs = implode('#',$pass_subj);
The result will be:
AP#AP,ENG#AP,ENG,FIL#AP,FIL,MATH,ENG#AP,FIL,ENG,MATH,SCI