编程需要的数学基础:谢谢各位了,帮我能正确的说明下.毕业真的不容易呀..谢谢.....,这个是用VFP6.0做的.

do case
case thisform.combo1.value='adminer'
thisform.grid1.RecordSource='adminer'
thisform.grid1.refresh
case thisform.combo1.value='course'
thisform.grid1.RecordSource='course'
thisform.grid1.refresh
case thisform.combo1.value='dept'
thisform.grid1.RecordSource='dept'
thisform.grid1.refresh
case thisform.combo1.value='sc'
thisform.grid1.RecordSource='sc'
thisform.grid1.refresh
case thisform.combo1.value='stu'
thisform.grid1.RecordSource='stu'
thisform.grid1.refresh
endcase
thisform.combo1.enabled=.F.
thisform.command1.enabled=.F.
thisform.command2.enabled=.F.
thisform.command3.enabled=.T.
thisform.command4.enabled=.T.

灰色的“增加&删除”的代码为：
thisform.grid1.enabled=.T.
thisform.grid1.allowaddnew=.T.
thisform.grid1.setfocus

灰色的“确定&退出”的click的代码为：
use
thisform.grid1.enabled=.F.
thisform.grid1.allowaddnew=.F.
thisform.grid1.recordsource=''
thisform.grid1.refresh
thisform.command1.enabled=.T.
thisform.command2.enabled=.T.
thisform.command3.enabled=.F.
thisform.command4.enabled=.F.
thisform.combo1.enabled=.T.
thisform.combo1.setfo us
谢谢......了......说明下是什么意思呀...