PHP echo不会出现在一台计算机上？

Question

I have a php script that queries a MySQL database and populates a drop-down menu using the data received. Everything was working fine and suddenly, the echo "Custom" option doesn't show up for me. I asked someone else to check the same page, and it showed up for him. I tried changing browsers, and nothing. Does anyone know why this would happen?

echo '<div class="c_element" style="height: auto;"> 
    <select class="c_sel">';
        $c= mysql_query("SELECT * FROM C WHERE c_lo_id =".$sel_lo_id) or die(mysql_error());

        while($row = mysql_fetch_array($c))
        {
            echo '<option value='.$row['c_id'].'>'.$row['c_name'].'</option>';              
        }

        echo '<option value="0">Custom </option>
    </select>';

Answer 1

This can happen if your values contain characters that break your html, like ', > or <. When outputting to html, you should always make sure that these are encoded correctly.

Apart from that this would also happen if there are spaces in your values as you don't quote the attribute value.

With both corrections:;

 echo '<option value="'.htmlspecialchars($row['c_id']).'">'.htmlspecialchars($row['c_name']).'</option>';
                     ^ added as well                    ^