PHP复选框检查挣扎

OK I don't know what I'm doing wrong, I'm trying to modify the css when the checkbox is crossed.

Here is the HTML code:

<input type='submit' name='com' value="Ajouter commentaire" />
<input type="checkbox" name="checkboxh">

PHP:

if( isset($_POST['com']) && isset($_POST['checkboxh']) )
{
echo '<style type="text/css">
    #com {
        display: none;
    }
    </style>';
}
else
{
//do smth else
}

After checking checkbox and pushing submit, the div is still visible.

You need to add the id="com" attribute to the div.