【发布时间】：2013-07-14 06:17:05
【问题描述】：
我正在从MySQL database 中提取数据，我的脚本会使用不同的维护更改填充选择菜单，并在 textarea 字段中加载更改说明。当页面第一次加载一切正常，但在用户选择更改类型后，它会动态加载更改的描述，BUT 不会再次使用更改选项填充选择菜单。
这就是我想要发生的事情：我希望即使在选择事件之后，选择菜单也能重新加载不同类型的更改。
我正在使用带有 html 的 php 和用于事件更改的 javascript。
有人可以建议我纠正我的代码需要什么吗？
数据库表是change_type
列是changeID changeType description
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta name="keywords" content="" />
<meta name="description" content="" />
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<title>Change Type</title>
<!--[if IE 6]>
<link href="default_ie6.css" rel="stylesheet" type="text/css" />
<![endif]-->
<script language="JavaScript" type="text/javascript">
function getData(combobox){
var value = combobox.options[combobox.selectedIndex].value;
// TODO: check whether the textarea content has been modified.
// if so, warn the user that continuing will lose those changes and
// reload a new page, and abort function if so instructed.
document.location.href = '?change_type='+value;
}
</script>
</head>
<?php
$conn = mysql_connect("localhost", "username", "password");
if (!$conn) {
echo "Unable to connect to DB: " . mysql_error();
exit;
}
if (!mysql_select_db("change")) {
echo "Unable to select mydbname: " . mysql_error();
exit;
}
error_reporting(E_ALL);
if (!mysql_ping()) {
die ("The MySQL connection is not active.");
}
mysql_set_charset('utf8');
// $_REQUEST is both _GET and _POST
if (isset($_REQUEST['change_type'])) {
$change_type = mysql_real_escape_string($_REQUEST['change_type']);
} else {
$change_type = False;
$query = "SELECT changeID, changeType FROM change_type;";
$exec = mysql_query($query); // You need to be already connected to a DB
if (!$exec) {
trigger_error("Cannot fetch data from change_type table: " . mysql_error(), E_USER_ERROR);
}
if (0 == mysql_num_rows($exec)) {
trigger_error("There are no changes in the 'change_type' table. Cannot continue: it would not work. Insert some changeids and retry.", E_USER_ERROR);
}
$options = '';
while($row = mysql_fetch_array($exec))
{
// if the current pageid matches the one requested, we set SELECTED
if ($row['changeID'] === $change_type)
$sel = 'selected="selected"';
else
{
// If there is no selection, we use the first combo value as default
if (False === $change_type)
$change_type = $row['changeID'];
$sel = '';
}
$options .= "<option value=\"{$row['changeID']}\" $sel>{$row['changeType']}</option>";
}
mysql_free_result($exec);
}
if (isset($_POST['change_data']))
{
$change_data = mysql_real_escape_string($_POST['change_data']);
$query = "INSERT INTO change_type ( changeID, description ) VALUE '{$change_type}', '{$change_data}' ) ON DUPLICATE KEY UPDATE description=VALUES(description);";
if (!mysql_query($query))
trigger_error("An error occurred: " . mysql_error(), E_USER_ERROR);
}
// Anyway, recover its desciption (maybe updated)
$query = "SELECT description FROM change_type WHERE changeID='{$change_type}';";
$exec = mysql_query($query);
// who says we found anything? Maybe this id does not even exist.
if (mysql_num_rows($exec) > 0)
{
// if it does, we're inside a textarea and we directly output the text
$row = mysql_fetch_array($exec);
$textarea = $row['description'];
}
else
$textarea = '';
mysql_free_result($exec);
?>
<body>
<div id="page-wrapper">
<div id="change_type">
<div id="description2">
<h2>Edit Your Description Here</h2>
<script type="text/javascript" src="../ckeditor/ckeditor.js"></script>
<form name="editpage" method="POST" action="email_form.php">
<table border="1" width="100%">
<tr>
<td>Change Type:</td>
<td>
<select name="change_type" onChange="getData(this)"><?php print $options; ?></select>
</td>
</tr>
<tr>
<td><textarea name="description" cols="80" row="8" id="description"><?php print $textarea; ?></textarea></td>
</tr>
<tr>
<td><input type="Submit" value="Save the page"/></td>
</tr>
</table>
</form>
</div>
</div>
</div>
</body>
</html>
【问题讨论】：
-
嘎克。有一天，你应该考虑使用 Java、Spring、Hibernate、JSTL——它比这种可怕的口香糖要清楚得多。
-
使用 JQuery 和 AJAX 而不是单独使用 javascript。
-
我对JQuery或Ajax不熟悉，你能举个例子吗？可以满足我想要发生的事情？
-
@BryceTurng 这里有很多示例搜索这两个术语，您会找到使用 ajax 和 jquery 的下拉示例。
标签： php mysql html textarea onchange