有人可以告诉我为什么打开此页面时没有显示任何内容吗?
<?php
include_once("functions.php");
// Process
$action = isset($_POST["action"]) ? $_POST["action"] : "";
if (empty($action))
{
// Send back the contact form HTML
$output = "<form action='#' style='display:none'>
<label for='image'>upload: </label>
<input type='file' id='image' name='image' maxlength=50>";
}
echo $output;
?>