queryformunit.pas

学生信息管理系统是使用DELPHI集成环境编写的一款软件

unit QueryFormUnit;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ExtCtrls, DBCtrls, Grids, DBGrids, StdCtrls, Buttons, ComCtrls;

type
  TQueryForm = class(TForm)
    PageControl1: TPageControl;
    TabSheet1: TTabSheet;
    TabSheet2: TTabSheet;
    TabSheet3: TTabSheet;
    RadioGroup1: TRadioGroup;
    GroupBox1: TGroupBox;
    Edit1: TEdit;
    BitBtn1: TBitBtn;
    DBGrid1: TDBGrid;
    DBNavigator1: TDBNavigator;
    BitBtn2: TBitBtn;
    RadioGroup2: TRadioGroup;
    GroupBox2: TGroupBox;
    BitBtn3: TBitBtn;
    DBGrid2: TDBGrid;
    DBNavigator2: TDBNavigator;
    Edit2: TEdit;
    DBGrid3: TDBGrid;
    DBNavigator3: TDBNavigator;
    Label1: TLabel;
    Label2: TLabel;
    Edit3: TEdit;
    BitBtn4: TBitBtn;
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
    procedure BitBtn3Click(Sender: TObject);
    procedure BitBtn4Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  QueryForm: TQueryForm;

implementation
uses
QueryDataModuleUnit;

{$R *.dfm}

procedure TQueryForm.BitBtn1Click(Sender: TObject);
begin
 With QueryDataModule do
 begin
    case RadioGroup1.ItemIndex of
 0: with StudentsQuery do
    begin
      Close;
      if sql.Count=3 then SQL.Delete(2);
      SQL.Append('where SNo=:tt');
      ParamByName('tt').AsString:=Edit1.Text;
      Prepare;
      Open;
      DBNavigator1.DataSource:=DataSourceStudent;
      DBGrid1.DataSource:=DataSourceStudent;
    end;
  1:With TeachersQuery do
    begin
      Close;
      if Sql.Count=3 then SQl.Delete(2);
      SQL.Append('Where TNo=:tt');
      ParamByName('tt').AsString:=Edit1.Text;
      Prepare;
      ShowMessage(inttostr(RadioGroup1.ItemIndex));
      Open;
      DBNavigator1.DataSource:=DataSourceTeacher;
      DBGrid1.DataSource:=DataSourceTeacher;
    end;
  2: with CourseQuery do
    begin
      Close;
      if Sql.Count=3 then SQL.Delete(2);
      SQL.Append('Where CNo=:tt');
      ParamByName('tt').AsString:=Edit1.Text;
      Prepare;
      Open;
      DBNavigator1.DataSource:=DataSourceCourse;
      DBGrid1.DataSource:=DataSourceCourse;
      end;
      end;
    end;
end;

procedure TQueryForm.BitBtn2Click(Sender: TObject);
begin
close;
end;

procedure TQueryForm.BitBtn3Click(Sender: TObject);
begin
 With QueryDataModule do
 begin
    case RadioGroup2.ItemIndex of
 0: with StudentsQuery do
    begin
      Close;
      if sql.Count=3 then SQL.Delete(2);
      SQL.Append('where Name=:tt');
      ParamByName('tt').AsString:=Edit2.Text;
      Prepare;
      Open;
      DBNavigator2.DataSource:=DataSourceStudent;
      DBGrid2.DataSource:=DataSourceStudent;
    end;
  1:With TeachersQuery do
    begin
      Close;
      if Sql.Count=3 then SQl.Delete(2);
      SQL.Append('Where Nane=:tt');
      ParamByName('tt').AsString:=Edit2.Text;
      Prepare;
      ShowMessage(inttostr(RadioGroup2.ItemIndex));
      Open;
      DBNavigator2.DataSource:=DataSourceTeacher;
      DBGrid2.DataSource:=DataSourceTeacher;
    end;
  2: with CourseQuery do
    begin
      Close;
      if Sql.Count=3 then SQL.Delete(2);
      SQL.Append('Where CName=:tt');
      ParamByName('tt').AsString:=Edit2.Text;
      Prepare;
      Open;
      DBNavigator2.DataSource:=DataSourceCourse;
      DBGrid2.DataSource:=DataSourceCourse;
      end;
      end;
    end;
end;

procedure TQueryForm.BitBtn4Click(Sender: TObject);
begin
With QueryDataModule.SpecialQuery do
begin
  Close;
  SQL.Clear;
  SQL.Add('SELECT Teacher.TNane,Teaching.Grade,Student.Name');
  SQL.Add('FROM"Student.db" Student');
  SQL.Add('INNER JOIN" Teaching.db" Teaching');
  SQl.Add('ON(Teaching.SNo=Student.SNo)');
  SQL.Add('INNER JOIN"Teacher.db"Teacher');
  SQL.Add('ON(Teacher.TNo=Teaching.TNo)');
  SQL.Add('Where Teacher.TNane=:gg');
  ParamByName('gg').AsString:=Edit3.Text;
  Prepare;
  Open;
end;
end;

end.