如何正确禁用HTML下拉选择框（Select）

<?php 
if($_SESSION['id'] == $all_information['complain_from']){ ?>
    <select name="complain_form" class="custom-select">
        <!-- 错误示例：readonly属性对option无效 -->
        <option value="<?php echo $all_information['complain_from']; ?>" readonly><?php echo $_SESSION['real_name']; ?></option>
    </select>
<?php }else{ ?>
    <select name="complain_form" class="custom-select">
        <option value="" disabled selected>Select a name</option>
<?php
foreach($all_account_info as $account_info){ ?>
        <!-- 错误示例：readonly属性对option无效 -->
        <option value="<?php echo $account_info['id']; ?>" <?php if($all_information['complain_from'] == $account_info['id']){ echo 'selected="selected"'; } ?> readonly>
<?php 
    echo $account_info['real_name']; 
?>
        </option>
    </select>
<?php } ?>

<?php 
// 假设在特定条件下需要禁用下拉框
if($_SESSION['id'] == $all_information['complain_from']){ ?>
    <select name="complain_form" class="custom-select" disabled>
        <!-- 此时option上的readonly属性已无意义，且通常不需要 -->
        <option value="<?php echo $all_information['complain_from']; ?>"><?php echo $_SESSION['real_name']; ?></option>
    </select>
<?php } else { 
    // 其他情况，下拉框可交互
?>
    <select name="complain_form" class="custom-select">
        <option value="" disabled selected>Select a name</option>
<?php
foreach($all_account_info as $account_info){ ?>
        <option value="<?php echo $account_info['id']; ?>" <?php if($all_information['complain_from'] == $account_info['id']){ echo 'selected="selected"'; } ?>>
<?php 
    echo $account_info['real_name']; 
?>
        </option>
<?php } ?>
    </select>
<?php } ?>