将值从数据库导入到选择中

Question

Good morning;

I´m trying to load some values from a mysql database to a "select", inside a form with HTML, PHP and some javascript.

I´m doing a school project and I need some names that are registered on the database. When I click on the select i want them to appear, so I can register one class and give them a class director (i´m not sure if that is called like that in english). When I "edit" the class, i want the select to put the value that are on the database and I want it to let me change the value.

I have a function file that help me with the functions that I use on the website, and I made de select code like this.

function DBConnect ()
{
    $db = mysqli_connect (DB_SERVER, DB_USERNAME, DB_PASSWORD, DB_DATABASE) or die (mysqli_connect_error());
    return $db;
}

function DBClose($db)
{
    mysqli_close($db) or die (mysqli_error($db));
}

function DBExecute($sql)
{
    $db = DBConnect();
    $result = mysqli_query($db,$sql);
    DBClose($db);
    return $result;
}

function DBRead11()
{
    $sql="SELECT nome FROM user_especial";
    $result=DBExecute($sql);

    while($res=mysqli_fetch_assoc($result))
    {
        $dts[]=$res;
    }
    return $dts;
}

And the code that I used on the php page so the select could "spawn" the values is this one:

<select name="diretor_turma" id="diretor_turma" required class="input-field4">
    <?php echo $dts; ?>
</select>

My database looks like the table that I puted on the first imgur link. Can someone help me? Thank you.

Answer 1

If I get your problem correctly the issue is that $dts is not known in the HTML select element because it is only in the function scope of DBRead11 . Therefore, before getting the value of $dts , you need to call the function DBRead11() and save the returned value into $dts . After that, because the array $dts should contain the attribute nome of all rows in the database, you can loop through all entries of $dts (eg with foreach() ) and construct a HTML option element from the value at the specific index.

In addition to that, I think you need to initialize $dts in your DBRead11 function as $dts = array() or $dts = [] before adding values to it.

function DBRead11() {
  $sql="SELECT nome FROM user_especial";
  $result=DBExecute($sql);

  $dts = mysqli_fetch_assoc($result);

  return $dts;
  }

<?php $dts = DBRead11(); ?>
<select name="diretor_turma" id="diretor_turma" required class="input-field4">
  <?php
    foreach($dts as $option) {
  ?>
    <option value="<?php echo $option['nome']; ?>"><?php echo $option['nome']; ?></option>
  <?php
    }
  ?>
</select>

As @M.Hemant already asked, please provide a var_dump() of the $dts variable. Otherwise, I can't tell exactly if just outputting $option (every a single element of $dts) is sufficient.