级联下拉框不工作php [英] Cascading drop down box not working php

问题描述

我在页面上有级联下拉框但是当选择第一个下拉值时它不会返回数据。

I have cascading drop down box on a page but it not return data when first drop down value is selected.

 <?php
                                                      $project_name=mysql_query("select main_unit_id,project_name from main_unit");
?>
<select name="project" id="project" tabindex="1">
 <option value=''>--Select Project --</option>
<?php while($rows=mysql_fetch_array($project_name)) { ?>
<option value="<?php echo $rows['main_unit_id']; ?>"><?php echo $rows["project_name"]; ?></option>
<?php } ?>
?>
<select>


<div id="activity"></div>

<script src="js/jquery-1.9.0.min.js"></script>
  <script language="javascript">
  $(document).ready(function(){
  $("select#project").change(function(){

    var main_unit_id =  $("select#project option:selected").attr('value');
    $("#activity").html( "" );
    if (main_unit_id.length > 0 ) {
      alert(main_unit_id);
     $.ajax({
        type: "POST",
        url: "fetch_activity.php",
        data: "main_unit_id="+main_unit_id,
        cache: false,
        success: function(html) {
          $("#activity").html(html);
        }
      });
    }
  });
  });
  </script>

和fetch_activity.php是

and fetch_activity.php is

<?php
include "conn/conn.php";
$main_unit_id = trim(mysql_escape_string($_POST["main_unit_id"]));
$sql = SELECT activity_id, activity_name FROM activities WHERE main_unit_id = '".$main_unit_id."'";
$count = mysqli_num_rows( mysqli_query($con, $sql) );
if ($count > 0 ) {
$query = mysqli_query($con, $sql);
?>
<label>
<select name="activity" id="activity">
  <option value="">Please Activity</option>
  <?php while ($rs = mysqli_fetch_array($query, MYSQLI_ASSOC)) { ?>
  <option value="<?php echo $rs["activity_id"]; ?>"><?php echo $rs["activity_name"]; ?></option>
  <?php } ?>
</select>
</label>
<?php
  }
?>

推荐答案

project_name = mysql_query（ 从main_unit中选择main_unit_id，project_name）;
？>
< 选择 名称 = 项目 id = 项目 tabindex = 1 > ;
< 选项 value =' ' > - 选择项目 - < / option >
<？ php while（

project_name=mysql_query("select main_unit_id,project_name from main_unit"); ?> <select name="project" id="project" tabindex="1"> <option value=''>--Select Project --</option> <?php while(

rows = mysql_fetch_array（

rows=mysql_fetch_array(

project_name））{？>
< 选项 value = <？php echo

project_name)) { ?> <option value="<?php echo

这篇关于级联下拉框不工作php的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！