问题描述
亲爱的程序员，
我正在为计算机学院制作学生注册表。我有两个下拉列表，一个用于讲座，另一个用于可用课程。我在数据库1表中创建了两个表，当他点击提交时保存学生的所有信息，另一个是课程表。
课程表的结构是：
lectTime ---------- SoftwareLab ----------- HardwareLab
MondayAM ------- MSoffice --- ------------ NULL
TuesdayAM ------- C语言------------ BasicHardware
WednesdayAM ---- MSoffice --------------- CCNA
MondayPM ------- VisualBasic -------- ---- Null
ThursdayPM ----- Null -------------------基本硬件
在我的第一个下拉列表中（即讲座）我有我所有的讲课时间（星期一，星期二，星期三，星期一和星期四）。现在我的要求是如果用户选择任何讲座 - 对于Ex：MondayAM，然后在另一个下拉列表中它应该是可用课程（MS-office），如果选择TuesdayAM那么它应该显示两个值（C-Language，BasicHardware）。 />
另一项要求是在我的注册表中，它不应允许每天每门课程插入超过20条记录。（例如，MondayAM-MSoffice只允许20名学生，TuesdayAM-C-Language 20名学生和BasiHardware 20名学生允许）。
任何人都可以用代码解决这个问题。
提前致谢
Dear Programmers,
I am making a student registration form for a computer institute. In which I have two dropdown lists, one is for lecturetimings and another is for availablecourses. I made two tables in database 1 table will save all the information of student when he clicks on submit, another is courses table.
The structure of courses table is:
lectTime ----------SoftwareLab-----------HardwareLab
MondayAM-------MSoffice---------------NULL
TuesdayAM-------C-Language------------BasicHardware
WednesdayAM----MSoffice---------------CCNA
MondayPM-------VisualBasic------------Null
ThursdayPM-----Null-------------------Basic Hardware
In my first dropdown list(i.e "lecturetimings") I have all my lecture timings(MondayAM, TuesdayAM,WednesdayAM, MondayPM and ThursdayPM). Now my requirement is if a user selects any lecturetimings-for Ex:MondayAM, then in another dropdown list it should available course(MS-office), if selectes TuesdayAM then it should show two values(C-Language, BasicHardware).
And another requirement is in my register table it should not allow to insert more than 20 records for each course of each day.(For example MondayAM-MSoffice only 20 students are allowed, TuesdayAM-C-Language 20 students and BasiHardware 20 students allowed).
Anyone kindly solve this with the code.
Thanks in advance
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