我正在创建一个带有四个下拉选择框的游戏启动窗体。每个框将用于选择一个播放器（播放器从mysql数据库中用户的朋友列表中提取）。我使用php动态填充选项列表（潜在玩家）。
每个项目都有一个唯一的名称和id。
有没有办法删除已经从其他下拉列表中选择的选项？我可以在这里找到javascript的例子，但在php中没有。
我已经插入了我正在使用的表单代码$选项只是一个用户名数组(注意：我的if语句完全是猜测。我绝对不是一个经验丰富的程序员。）

<form method="POST" action="game.php">
         <select id="1stPlayer" name="1stPlayer" required>
             <option value="" disabled="disabled" selected="selected">Please select Player 1 (Team 1)</option>
                <?php

                $first = $_GET["1stPlayer"];
                $second = $_GET["2ndPlayer"];
                $third = $_GET["3rdPlayer"];
                $fourth = $_GET["4thPlayer"];

                echo implode(",",array_unique($option));

                 foreach ($option as $row) {
                   $value = $row;
                     if ($value != $second && $value != $third && $value != $fourth ) {
                       echo '<option value="'. $value .'">'. $value .'</option>';
                       };
                     };
             ?>
           </select>
           <select id="2ndPlayer" name="2ndPlayer" required>
               <option value="" disabled="disabled" selected="selected">Please select Player 1 (Team 1)</option>
                  <?php

                  $first = $_GET["1stPlayer"];
                  $second = $_GET["2ndPlayer"];
                  $third = $_GET["3rdPlayer"];
                  $fourth = $_GET["4thPlayer"];

                  echo implode(",",array_unique($option));

                   foreach ($option as $row) {
                     $value = $row;
                       if ($value != $first && $value != $third && $value != $fourth ) {
                         echo '<option value="'. $value .'">'. $value .'</option>';
                         };
                       };
               ?>
             </select>
             <select id="$third" name="$third" required>
                 <option value="" disabled="disabled" selected="selected">Please select Player 1 (Team 1)</option>
                    <?php

                    $first = $_GET["1stPlayer"];
                    $second = $_GET["2ndPlayer"];
                    $third = $_GET["3rdPlayer"];
                    $fourth = $_GET["4thPlayer"];

                    echo implode(",",array_unique($option));

                     foreach ($option as $row) {
                       $value = $row;
                         if ($value != $second && $value != $first && $value != $fourth ) {
                           echo '<option value="'. $value .'">'. $value .'</option>';
                           };
                         };
                 ?>
               </select>
               <select id="4thPlayer" name="4thPlayer" required>
                   <option value="" disabled="disabled" selected="selected">Please select Player 1 (Team 1)</option>
                      <?php

                      $first = $_GET["1stPlayer"];
                      $second = $_GET["2ndPlayer"];
                      $third = $_GET["3rdPlayer"];
                      $fourth = $_GET["4thPlayer"];

                      echo implode(",",array_unique($option));

                       foreach ($option as $row) {
                         $value = $row;
                           if ($value != $second && $value != $third && $value != $first ) {
                             echo '<option value="'. $value .'">'. $value .'</option>';
                             };
                           };
                   ?>
                 </select>
              <input type="submit" name="startGame" id="single_game_button" value="Start Game">
            </form>