unit5.pas

本例是用delphi开发的学生与课程信息管理系统

unit Unit5;

interface

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

type
  TFormcou_alt = class(TForm)
    Querycou_alt: TQuery;
    DataSourcecou_alt: TDataSource;
    DBGridcou_alt: TDBGrid;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Label1: TLabel;
    GroupBox1: TGroupBox;
    Label2: TLabel;
    Label3: TLabel;
    Label4: TLabel;
    Label5: TLabel;
    Editcno: TEdit;
    Editcname: TEdit;
    ComboBoxsem: TComboBox;
    Editcbook: TEdit;
    Button5: TButton;
    Button6: TButton;
    GroupBox2: TGroupBox;
    Label6: TLabel;
    Editcno1: TEdit;
    Label7: TLabel;
    Editkey_set: TEdit;
    ComboBoxkey: TComboBox;
    Label8: TLabel;
    Button7: TButton;
    Button8: TButton;
    procedure Button5Click(Sender: TObject);
    procedure Button6Click(Sender: TObject);
    procedure DBGridcou_altCellClick(Column: TColumn);
    procedure Button7Click(Sender: TObject);
    procedure Button8Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Formcou_alt: TFormcou_alt;

implementation

{$R *.dfm}

procedure TFormcou_alt.Button5Click(Sender: TObject);
var
  cno,cname,sem,cbook:string;
begin
  cno:=editcno.Text+'%';
  cname:=editcname.Text+'%';
  sem:=comboboxsem.Text+'%';
  cbook:=editcbook.Text+'%';
  with querycou_alt do
    begin
      close;
      sql.Clear;
      sql.add('select * from course');
      sql.add('where(cno like :cnoname)and(cname like :cnamename)and(sem like :semname)and(cbook like :cbookname)');
      sql.Add('order by cno');
      parambyname('cnoname').AsString:=cno;
      parambyname('cnamename').AsString:=cname;
      parambyname('semname').AsString:=sem;
      parambyname('cbookname').AsString:=cbook;
      prepare;
      open;

    end;
end;

procedure TFormcou_alt.Button6Click(Sender: TObject);
begin
  editcno.Text:='';
  editcname.Text:='';
  comboboxsem.Text:='';
  editcbook.text:='';
  with querycou_alt do
    begin
      close;
      sql.Clear;
      sql.Add('select * from course');
      sql.add('order by cno');
      prepare;
      open;
    end
end;

procedure TFormcou_alt.DBGridcou_altCellClick(Column: TColumn);
begin
 editcno1.Text:=dbgridcou_alt.fields[0].asstring;
 comboboxkey.Text:='';
 editkey_set.Text:='';
end;

procedure TFormcou_alt.Button7Click(Sender: TObject);
var
  key,key_set:string;
  cno:string;
begin
  cno:=editcno1.Text;
  key:=comboboxkey.Text;
  key_set:=editkey_set.Text;
  if (cno='')or(key='')or(key_set='')then
    showmessage('请将修改信息输入完全！')
  else
    begin

    if key='cname' then
     begin
      with querycou_alt do
        begin
          close;
          sql.Clear;
          sql.add('update course set cname=:key_setname');
          sql.add('where cno=:cnoname');
          parambyname('key_setname').AsString:=key_set;
          parambyname('cnoname').AsString:=cno;
          prepare;
          execsql;
        end;

     end
    else if key='sem'then
      begin

       with querycou_alt do
         begin
           close;
           sql.Clear;
           sql.Add('update course set sem=:key_setname');
           sql.Add('where cno=:cnoname' );
           parambyname('key_setname').asstring:=key_set;
           parambyname('cnoname').AsString:=cno;
           prepare;
           execsql;
          end;

         end
    else if key='cbook' then
      begin
         with querycou_alt do
           begin
             close;
             sql.Clear;
             sql.add('update course set cbook=:key_setname');
             sql.add('where cno=:cnoname');
             parambyname('key_setname').AsString:=key_set;
             parambyname('cnoname').asstring:=cno;
             prepare;
             execsql;
           end;
           
        end;
       with querycou_alt do
      begin
        close;
        sql.Add('select * from course');
        sql.add('order by cno');
        prepare;
        open;
      end;
    end;

end;

procedure TFormcou_alt.Button8Click(Sender: TObject);
begin
  close;
end;

end.