How to display buttons only when checked - php

Question

I am working on an assignment. I need to display buttons using jquery only when the checkbox is checked and only for few subjects. All the subjects are coming from the backend using php and mysql. The table is getting subjects dynamically.
I want to display button or text only when few of the subjects are checked
Here is the code
<?php
if($stmt = $conn->prepare("SELECT classid, code, name, teacher, classroom,
time, cost FROM classes ORDER BY classid")){
// $stmt->bind_param("isssssd");
$result = $stmt->execute();
$stmt->bind_result($classid, $code, $name, $teacher, $classroom, $time,
$cost);
$checked = "";
while ($stmt->fetch()) {
$row = array("classid"=>$classid, "code"=>$code, "name"=>$name,
"teacher"=>$teacher, "classroom"=>$classroom, "time"=>$time, "cost"=>$cost);
if(in_array($classid, $selectedclasses)){
$checked = "checked";
}else{
$checked = "";
}
?>
<div class="row col-md-12">
<hr/>
</div>
<div class="row col-md-12" id="class_<?php echo $classid; ?>">
<div class="col-md-4 col-lg-4 col-sm-6 col-sx-6">
<input type="checkbox" id="classitem_<?php echo $classid; ?>"
name="classitem_<?php echo $classid; ?>" class="classitem" value="<?php echo
$classid; ?>" <?php echo $checked; ?> > <?php echo $name; ?>
</div>
<div class="col-md-2 col-lg-2 col-sm-6 col-sx-6">
<?php echo $teacher; ?>
</div>
<div class="col-md-2 col-lg-2 col-sm-6 col-sx-6">
<?php echo $cost; ?>
</div>
<div id="mine" class="col-md-4 col-lg-4 col-sm-6 col-sx-6">
<?php echo $time; ?>
</div>
</div>
<?php
}
$stmt->close();
}
?>

Answer 1

you need to try something like given below.
$(function()
{
$('[name="products_id"]').change(function()
{
if ($(this).is(':checked')) {
$("#demo").css('display', 'block');
}
else{
$("#demo").css('display', 'none');
}
});
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js"></script>
<button type="submit" id="demo" class="btn btn-success" name="export_all" style="display: none;">click</button>
<input class="form-check-input" type="checkbox" value="" id="defaultCheck1" name='products_id'>