如何使用PHP创建多个依赖的下拉列表,并将数据保存在mysql数据库中


how to create a multiple dependent drop down list using php and save the data in mysql database?

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns = "http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv = "Content-Type" content = "text/html; charset=iso-8859-1" />
<title>Sections Demo</title>
<script type = "text/javascript" src = "http://ajax.googleapis.com/
ajax/libs/jquery/1.4.2/jquery.min.js"></script>
<script type="text/javascript">
    $(document).ready(function()
    {
        $(".state").change(function()
        {
            var id = $(this).val();
            var dataString = 'id=' + id;
            $.ajax
            ({
                type: "POST",
                url: "ajax_city.php",
                data: dataString,
                cache: false,
                success: function(html)
                {
                    $(".district").html(html);
                }
            });
        });
    });
</script>
<style>
    label
    {
        font-weight:bold;
        padding:10px;
    }
</style>
</head>
<body>
    <div style="margin:80px">
        <label>state :</label> <select name="country" class="country">
            <option selected="selected">--Select state--</option>
            <?php
                include('db.php');
                $sql = mysql_query("select id,data from states where weight='1'");

                while ($row = mysql_fetch_array($sql)) {
                    $id = $row['id'];
                    $data = $row['data'];
                    echo '<option value="' . $id . '">' . $data . '</option>';
                }
            ?>
        </select> <br/><br/>
        <label>district :</label> <select name="district" class="district">
            <option selected="selected">--Select district--</option>
        </select>
    </div>
</body>
</html>

我试图创建一个多个下拉列表,其中每个下拉列表都依赖于前一个下拉列表…例如:我想创建一个州的下拉列表,当选择一个州时,该州的地区将在下一个下拉列表中列出,所选数据将存储在数据库中…有人能帮我解决一下吗?提前感谢……: -)

它不会返回false,因为ajax方法是异步的,它不会等待成功事件发生。可以使用

命令使ajax同步
async: false

,但这不是一个好方法。它也会冻结浏览器