Post values from checkboxes [duplicate]

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• Getting checkbox values on submit 10 answers

I am trying to post values from multiple checkboxes into table. Unfortunately, I am getting an error which says:

Warning: Invalid argument supplied for foreach() in /opt/lampp/htdocs/WDT/survey.php on line 6

Here is my form:

<form action="survey.php" method="POST">
  <div class="input-select">
    <h3>Preferred mode of transport</h3>
    <select name="transportMode">
      <option value="Car">Car</option>
      <option value="Bus">Bus</option>
      <option value="Tram">Tram</option>
      <option value="Train">Train</option>
    </select>
  </div>
  <div class="input-radio">
    <h3>Chosen mode of transport to hostel</h3>
    <input type="radio" name="transportToHostel" value="car"> Car<br>
    <input type="radio" name="transportToHostel" value="taxi"> Taxi<br>
    <input type="radio" name="transportToHostel" value="other"> Other
  </div>
  <div class="input-checkbox">
    <h3>Required room equipment</h3>
    <input type="checkbox" name="requiredEquipment" value="double bed"> Double Bed<br>
    <input type="checkbox" name="requiredEquipment" value="kettle"> Kettle<br>
    <input type="checkbox" name="requiredEquipment" value="tv"> TV
  </div>
  <input type="submit" text="Send">
</form>

And PHP script:

if (!empty($_POST['transportMode'])) {
echo 'Transport Mode: '.$_POST['transportMode'].'<br>';
}
if (!empty($_POST['transportToHostel'])) {
    echo 'Transport to Hostel: '.$_POST['transportToHostel'].'<br>';
}


if(!empty($_POST['requiredEquipment'])) {
    foreach($_POST['requiredEquipment'] as $equipment){
       $equipment_required .= $equipment.',';
        echo "value : ".$_POST.'<br/>';
    }}

Thanks in advance!