Home Backend Development PHP Tutorial PHP+mysql实现二级级联上拉框的有关问题

PHP+mysql实现二级级联上拉框的有关问题

Jun 13, 2016 am 10:53 AM
gt lt mysql nbsp quot

PHP+mysql实现二级级联下拉框的问题
请教大虾门,PHP+mysql实现二级级联下拉框,解决班级很多的情况下,先选择入学年份再选择属于这一年的班级的问题。
  第一个下拉框中的年份可以读出来,但是当选择某一年之后,班级下拉框中什么都没有显示,代码如下,请大虾们看看问题出在哪儿,谢谢了先

/***********************************************
** 
** 数据库:数据库名(alumni)、数据表(enteryear、banji)
** 表enteryear中字段:enter_id(id编号)、entertime(年份)
** 表banji中的字段:id(id编号)、classnum(班级号)、enteryear(年份)
***********************************************/
//****************** 连接选择数据库 ***************
$link = mysql_connect("localhost", "root", "")
  or die("Could not connect : " . mysql_error()); 
mysql_select_db("alumni") or die("Could not select database");


//******************提取省份信息******************
$sqlSel = "select * from enteryear order by enter_id ";
$result = mysql_query($sqlSel) or die("Query failed : " . mysql_error()); 

$forum_data = array();
while( $row = mysql_fetch_array($result) )
{
  $forum_data[] = $row;
}
//print_r ($forum_data);
mysql_free_result($result);

//**************获取城市信息**************  
$sqlSel2 = "select * from banji order by id desc";

if( !($result2 = mysql_query($sqlSel2)) )
{
  die('Could not query t_city list');
}

$forum_data2 = array();
while( $row2 = mysql_fetch_array($result2) )
{
  $forum_data2[] = $row2;
}

mysql_free_result($result2);
?>


 


 
入学年份:




------解决方案--------------------
哦,我之前也遇到过类似问题,解决了就好,哈哈。。。
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