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HomeBackend DevelopmentPHP Tutorial PHP怎样做下拉列表的联动?解决办法

PHP怎样做下拉列表的联动?
比如我有个表,有2个字段,name ,班级 一个下拉列表从数据库读出班级的所有数据, 另一个下拉列表的数据根据班级读


出所有的name。 这个怎么做?

------解决方案--------------------
使用ajax 获取数据 js/jquery 更新页面内容
或者一次将所有数据读出来 写入页面... 显示相应的内容.
------解决方案--------------------
我总觉得你的表设计的有问题。
这个name 是班级的name还是学生的name ???
------解决方案--------------------
下拉菜单
onchange事件

然后用ajax向服务器请求
------解决方案--------------------
这跟PHP有啥关系? 自己搜三级联动去,一堆代码
------解决方案--------------------
学生跟班级不是一个东西,放在一张表了不合适。
student表:sid,sname,classid 
class表: classid,classname

第一个下拉菜单把class表读取,
用ajax联动,当第一个下拉菜单数据变更然后触发事件,根据后来选择的classid 去 student表查出所有的name值,在第二个菜单列出。

我不知道你说的name是做什么的。上面的只是大体说了下,如果有问题你就看一眼就算了。
嘿嘿。

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