unit14.pas

本例是用delphi开发的学生与课程信息管理系统

unit Unit14;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Grids, DBGrids, DB, ADODB;

type
  TFormsc_sel = class(TForm)
    ADOQuerysc_sel: TADOQuery;
    DataSourcesc_sel: TDataSource;
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Editsno: TEdit;
    Editsname: TEdit;
    ComboBoxsem: TComboBox;
    Button1: TButton;
    DBGridsc_sel: TDBGrid;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Button5: TButton;
    Button6: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button6Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Formsc_sel: TFormsc_sel;

implementation

{$R *.dfm}

procedure TFormsc_sel.Button1Click(Sender: TObject);
var
  sno,sname,sem,temp:string;
begin
  sno:=trim(editsno.text);
  sname:=trim(editsname.text);
  sem:=trim(comboboxsem.text);
  if (sno='')or(sname='')or(sem='') then
   begin
    showmessage('请将信息输入完全！');
   end
  else
    begin
      adoquerysc_sel.close;
      adoquerysc_sel.sql.clear;
      adoquerysc_sel.sql.add('select sno from student');
      adoquerysc_sel.sql.add('where sno='''+sno+''' and sname='''+sname+'''');
      adoquerysc_sel.open;
      temp:=adoquerysc_sel.fieldbyname('sno').asstring;
      if temp='' then
        showmessage('您输入的学号或姓名错误！')
      else
        begin
          button2.visible:=true;
          button3.visible:=true;
          button4.visible:=true;
          button5.visible:=true;
          dbgridsc_sel.visible:=true;
          if sem='all' then
            begin
              adoquerysc_sel.close;
              adoquerysc_sel.sql.clear;
              adoquerysc_sel.sql.add('select cno,cname,cbook,sem from viewsc where sno='''+sno+'''');
              adoquerysc_sel.sql.add('order by sem');
              adoquerysc_sel.open;
            end
          else
            begin
              adoquerysc_sel.close;
              adoquerysc_sel.sql.clear;
              adoquerysc_sel.sql.add('select cno,cname,cbook,sem from viewsc where sem='''+sem+'''and sno='''+sno+'''');
              adoquerysc_sel.sql.add('order by cno');
              adoquerysc_sel.open;
            end;
          
        end;
    end;
end;

procedure TFormsc_sel.Button6Click(Sender: TObject);
begin
  close;
end;

end.