Doubt to use combobox

Question

Good Morning,

I have a final chair work for web development, where I need to create a crud for teams, players, create a style table of the Brazilian championship and create the rounds. I’ve managed to create the Ruds and the championship table but create the rounds is complicated. I thought I’d create a combobox to make the matches and use textfield to insert the results, create this is easy the problem is how can I do when using combobox to not allow the same team twice in the same round and if the value of textfield then step to some field of the database. Or if you have a better idea to give, thank you all.

Answer 1

Here’s a very basic example. I think this will solve your problem, but understand the logic.
Javascript is responsible for hiding the selected option and replicating in the other selects. That way you don’t have to send a post every time you select an option

$('.select').on('change', function() {
  var option = $(this).val();
  $('.select').each(function() {
    $(this).find('option').show();
    $(this).find('option[value=' + option + ']').hide();
  });
});

<form action="#" method="POST">
  <select class='select' name="select[1][]">
    <option>Selecionar</option>
    <option value='A'>A</option>
    <option value='B'>B</option>
    <option value='C'>C</option>
    <option value='D'>D</option>
    <option value='E'>E</option>
  </select>
  <select class='select' name="select[1][]">
    <option>Selecionar</option>
    <option value='A'>A</option>
    <option value='B'>B</option>
    <option value='C'>C</option>
    <option value='D'>D</option>
    <option value='E'>E</option>
  </select>
  <br>
  <br>
  <input type="submit">
</form>

In PHP =>

  <?php
        echo '<pre>';
        print_r($_POST);
       echo '</pre>';
       exit;
/* Como o PHP vai capturar =>
    [select] => Array
            (
                [1] => Array
                    (
                        [0] => A
                        [1] => B
                    )

            )

*/
    ?>

NOTE: The result of this answer is also based on the comments of your question.
I’m waiting for feedback.