unit2.~pas

本例是用delphi开发的学生与课程信息管理系统

unit Unit2;

interface

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

type
  TFormstu_sel = class(TForm)
    Querystu_sel: TQuery;
    Label1: TLabel;
    DataSourcestu_sel: TDataSource;
    DBGridstu_sel: TDBGrid;
    GroupBox1: TGroupBox;
    Label2: TLabel;
    ComboBoxkey: TComboBox;
    Label3: TLabel;
    Editkey_set: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;
    Button4: TButton;
    Button5: TButton;
    Button6: TButton;
    Button7: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure ComboBoxkeyChange(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Formstu_sel: TFormstu_sel;

implementation

{$R *.dfm}

procedure TFormstu_sel.Button1Click(Sender: TObject);
var
  key,key_set:string;
begin
 key:=comboboxkey.text;
 key_set:=editkey_set.text;
 if(key='')and(key_set='')then
   with querystu_sel do
     begin
       close;
       sql.Clear;
       sql.Add('select * from student order by sno');
       prepare;
       open ;
     end
 else if(key<>'')and(key_set='')then
     showmessage('请输入''关键字设置''信息！') 
 else if(key='')and(key_set<>'')then
     showmessage('请选择''查询关键字选择''信息！')
 else
   begin
     key_set:=key_set+'%';
     if key='sno'then
       with querystu_sel do
         begin
           close;
           sql.Clear;
           sql.Add('select * from student where sno like :key_setname');
           sql.add('order by sno');
           parambyname('key_setname').AsString:=key_set;
           prepare;
           open;
         end
     else if key='sname'then
       with querystu_sel  do
         begin
           close;
           sql.clear;
           sql.Add('select * from student where sname like :key_setname');
           sql.add('order by sno');
           parambyname('key_setname').AsString:=key_set;
           prepare;
           open;
         end
     else if key='ssex'then
       with querystu_sel do
         begin
           close;
           sql.Clear;
           sql.Add('select * from student where ssex like :key_setname');
           sql.add('order by sno');
           parambyname('key_setname').AsString:=key_set;
           prepare;
           open;
         end
     else if key='sage'then
       with querystu_sel do
        begin
         close;
         sql.clear;
         sql.add('select * from student where sage like :key_setname');
         sql.add('order by sno');
         parambyname('key_setname').asstring:=key_set;
         prepare;
         open;
        end
     else if key='sdep'then
       with querystu_sel do
         begin
           close;
           sql.Clear;
           sql.Add('select * from student where sdep like :key_setname');
           sql.add('order by sno');
           parambyname('key_setname').AsString:=key_set;
           prepare;
           open;
         end;
      end;
end;

procedure TFormstu_sel.Button2Click(Sender: TObject);
begin
 close;
end;

procedure TFormstu_sel.ComboBoxkeyChange(Sender: TObject);
begin
  editkey_set.text:='';
end;

end.