php - 将组合框中的所选项目设置为 "please select..."

Question

我想添加“请选择...”作为组合框中的第一个选项。请参阅下面的代码 - 有什么建议吗？

问候，彼得

<?php

mysql_connect ("localhost", "username", "password"); 
mysql_select_db('mysqldb');

$sql = "SELECT data_id FROM projects";
$result = mysql_query($sql);

echo "<select name='data_id '>";
$sql[0] = 'Please select...';
while ($row = mysql_fetch_array($result)) 
{
    echo "<option value='" . $row['data_id '] . "'>" . $row['data_id'] . "</option>";
}
echo "</select>";

?>

Answer 1

替换 $sql[0] = 'Please select...';
对此 echo '<option value="" disabled>Please select...</option>';