How to enter several data received from the same field?

Question

I have a form in html that has a field where the user goes inserting the data as it shows the code below, this form is dynamic and the user can insert as much information as he wants, in the following case I put only six systems.

My question is: How will I receive this amount of information in PHP by $_POST and insert it into the database? The query I can do, but I know I have to work with a repetition structure, but how?

HTML code:

<div id="container">
<ul class="tags">
<li class="addedTag">
sistema1
<span class="tagRemove" onclick="$(this).parent().remove();">x</span>
<input type="hidden" value="sistema1" name="tags[]"/>
</li>
<li class="addedTag">
sistema2
<span class="tagRemove" onclick="$(this).parent().remove();">x</span>
<input type="hidden" value="sistema2" name="tags[]"/>
</li>
<li class="addedTag">
sistema3
<span class="tagRemove" onclick="$(this).parent().remove();">x</span>
<input type="hidden" value="sistema3" name="tags[]"/>
</li>
<li class="addedTag">
sistema4
<span class="tagRemove" onclick="$(this).parent().remove();">x</span>
<input type="hidden" value="sistema4" name="tags[]"/>
</li>
<li class="addedTag">
sistema5
<span class="tagRemove" onclick="$(this).parent().remove();">x</span>
<input type="hidden" value="sistema5" name="tags[]"/>
</li>
<li class="addedTag">
sistema6
<span class="tagRemove" onclick="$(this).parent().remove();">x</span>
<input type="hidden" value="sistema6" name="tags[]"/>
</li>
<li class="tagAdd taglist">
<input type="text" id="search-field"/>
</li>
</ul>
</div>

PHP:

<?php 

    $tags = $_POST['tags']; 
    $query = mysqli_query($dbc, ""INSERT INTO tb_conhecimentos .......
?>

Answer 1

That one form will return something like this:

Code:

<?php

    var_dump($_POST['tags']);

Exit:

array(6) { [0]=> string(8) "sistema1" 
           [1]=> string(8) "sistema2" 
           [2]=> string(8) "sistema3" 
           [3]=> string(8) "sistema4" 
           [4]=> string(8) "sistema5" 
           [5]=> string(8) "sistema6" }

---

How do you record these items?

With a foreach:

<?php

    foreach($_POST['tags'] as $value):
        echo $value;
    endforeach;

the $value would be every item shipped within that array of tags.

---

If the version of PHP for >= 5.2.0 can use filter_input:

<?php

    $tags = filter_input (INPUT_POST, "tags", FILTER_DEFAULT, FILTER_REQUIRE_ARRAY);
    foreach($tags as $value):
        echo $value;
    endforeach;