edit2.Text:=trim(adoquery1.fieldbyname('xm').AsString); edit3.Text:=trim(adoquery1.fieldbyname('bjmc').AsString); listcourse(id); //列出已选课程 //允许开始选课 bitbtn2.Enabled:=true; bitbtn3.Enabled:=true; //bitbtn4.Enabled:=true; end else begin
//只有在籍学生才能选课
showmessage('该生非在籍学生，不能选课'); bitbtn2.Enabled:=false; bitbtn3.Enabled:=false; id:=''; end; end; end;
//--------显示学生已经选的课程---------- procedure TCourseElect.listcourse(id: string); begin
//将符合选课条件的学生已经选过的课程列在表中 adoquery2.Close; adoquery2.SQL.Clear; adoquery2.SQL.Add('select
XSXX.xh,XKB.kxh,KCXX.kcmc,js,kkxb,KCB.sksjt,sksjj,skdd
from
KCB,XSXX,KCXX,XKB where XKB.kxh=KCB.kxh and XKB.xh=XSXX.xh and KCXX.kcbh=KCB.kcbh'); adoquery2.Open; end;
//---------------课程查询-------------------
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procedure TCourseElect.BitBtn1Click(Sender: TObject); begin
if(edit4.Text='')and(edit5.Text='')and(edit6.Text='')and(edit7.Text='')then showmessage('请输入查询条件！') else begin
adoquery3.Close; adoquery3.SQL.Clear; adoquery3.SQL.Add('select
KCB.kxh,KCXX.kcbh,kcmc,js,kkxb,pym,KCB.sksjt,sksjj,skdd KCB,XSXX,KCXX,XKB');
adoquery3.SQL.Add('where (XKB.kxh=KCB.kxh and XKB.xh=XSXX.xh and KCXX.kcbh=KCB.kcbh) KCXX.kcmc='''+edit5.Text+'''or XKB.kxh='''+edit7.Text+''')'); Adoquery3.Open;
if(Adoquery3.RecordCount=0)then showmessage('找不到这门课程！') else begin
DBGrid2.DataSource.DataSet:=Adoquery3; DBGrid2.DataSource.DataSet.Active:=false; DBGrid2.DataSource.DataSet.Active:=true; end; end; end;
//-----------将选择的课程添加到学生的选课表中-------------- procedure TCourseElect.BitBtn2Click(Sender: TObject); var num:string; day,section:integer;
and
(KCXX.pym='''+edit4.Text+'''or KCXX.kcbh='''+edit6.Text+'''or
from
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begin
//未选择课程时，不允许提交 if adoquery3.RecordCount=0 then begin
showmessage('请先选择一门课程'); exit; end;
num:=trim(dbgrid2.Fields[0].Text);//保存课序号
//判断所选的课程是否已选和是否与其他已经选的课程有时间冲突 adoquery1.Close; adoquery1.SQL.Clear;
adoquery1.SQL.Add('select sksjt,sksjj from KCB');
adoquery1.SQL.Add('where kcbh='''+dbgrid2.Fields[1].Text+''''); adoquery1.Open;
while not adoquery1.Eof do begin
day:=adoquery1.fieldbyname('sksjt').AsInteger; section:=adoquery1.fieldbyname('sksjj').AsInteger; adoquery2.First;
while not adoquery2.Eof do begin
//判断课程是否已选
if (trim(adoquery2.fieldbyname('kxh').AsString)=num) then begin
showmessage('所选的课程：'+trim(adoquery2.fieldbyname('kcmc').AsString)+' 已在课表中，请选择其他课程'); exit; end;
//判断课程是否与已选课程有时间冲突 if
(adoquery2.fieldbyname('sksjt').AsInteger=day)and(adoquery2.fieldbyname('sksjj').A
31
sInteger=section) then begin
showmessage('
所
选
课
程
的
上
课
时
间
与
已
选
的
'+trim(adoquery2.fieldbyname('kcmc').AsString)+' 冲突!'); exit; end;
adoquery2.Next; end;
adoquery1.Next; end; //选课
adocommand1.CommandText:='insert
values('''+id+''','''+trim(dbgrid2.Fields[0].Text)+''')'; adocommand1.Execute; listcourse(id);//刷新数据表 end;
//-------------删除已选课程-------------
procedure TCourseElect.BitBtn3Click(Sender: TObject); begin
if application.MessageBox('确实删除所选课程？','确定删除',MB_OKCANCEL)=IDOK then begin
adocommand1.CommandText:='delete
from
XKB
where
into
XKB([xh],[kxh])
(xh='''+trim(dbgrid3.Fields[0].Text)+''')and(kxh='''+trim(dbgrid3.Fields[1].Text)+''')'; adocommand1.Execute; listcourse(id);//刷现列表 end; end;
procedure TCourseElect.FormClose(Sender: TObject;
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