c_lb.pas

《delphi数据库设计与实例开发》随书光盘

unit c_lb;

interface

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

type
  Tcfrm_lb = class(TForm)
    GroupBox1: TGroupBox;
    Label1: TLabel;
    Label2: TLabel;
    e_id: TEdit;
    e_name: TEdit;
    DBGrid1: TDBGrid;
    Label4: TLabel;
    BitBtn1: TBitBtn;
    BitBtn2: TBitBtn;
    BitBtn3: TBitBtn;
    BitBtn4: TBitBtn;
    DataSource1: TDataSource;
    procedure FormCreate(Sender: TObject);
    procedure e_idKeyPress(Sender: TObject; var Key: Char);
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
    procedure DataSource1DataChange(Sender: TObject; Field: TField);
    procedure DBGrid1Enter(Sender: TObject);
    procedure BitBtn3Click(Sender: TObject);
    procedure BitBtn4Click(Sender: TObject);
    procedure FormClose(Sender: TObject; var Action: TCloseAction);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  cfrm_lb: Tcfrm_lb;
   mes:string;
implementation

uses datam;

{$R *.dfm}

procedure Tcfrm_lb.FormCreate(Sender: TObject);
begin
  dm.ADO_lb.Open;
  dm.ADO_lb.Sort:='编号';
end;

procedure Tcfrm_lb.e_idKeyPress(Sender: TObject; var Key: Char);
begin
 if not ( Key in ['0'..'9',#13,#8]) then Key := #0;
  if key=#13 then
   begin
    e_name.SetFocus();
   end;
end;

procedure Tcfrm_lb.BitBtn1Click(Sender: TObject);
begin
  BitBtn3.Tag:=1;
  e_id.Enabled:=true;
  e_name.Enabled:=true;
  e_id.Text:='';
  e_name.text:='';
  BitBtn1.enabled:=false;
  BitBtn2.Enabled:=false;
  BitBtn3.Enabled:=true;
  BitBtn4.Enabled:=false;
  e_id.SetFocus();
end;

procedure Tcfrm_lb.BitBtn2Click(Sender: TObject);
begin
  dm.ADO_vcd.Open;
  if dm.ADO_vcd.Locate('小类',e_name.Text,[])=true then
   begin
    application.messagebox(pchar('此类别已经使用，不可修改其内容！')
    ,pchar('提示'),MB_ICONEXCLAMATION);
    exit;
   end;
  dm.ADO_vcd.Close;
  Bitbtn3.Tag:=2;
  Bitbtn3.Enabled:=true;
  e_id.Enabled:=true;
  e_name.Enabled:=true;
  Bitbtn2.Enabled:=false;
  Bitbtn1.Enabled:=false;
  BitBtn4.Enabled:=false;
end;

procedure Tcfrm_lb.DataSource1DataChange(Sender: TObject; Field: TField);
begin
 e_id.Text:=dm.ADO_lb.fieldbyname('编号').asstring;
 e_name.text:=dm.ADO_lb.fieldbyname('类别').asstring;
end;

procedure Tcfrm_lb.DBGrid1Enter(Sender: TObject);
begin
  Bitbtn1.Enabled:=true;
  Bitbtn2.Enabled:=true;
  Bitbtn4.Enabled:=true;
  Bitbtn3.Enabled:=false;
  e_id.Enabled:=false;
  e_name.enabled:=false;
  //
  e_id.Text:=dm.ADO_lb.fieldbyname('编号').asstring;
  e_name.text:=dm.ADO_lb.fieldbyname('类别').asstring;
end;

procedure Tcfrm_lb.BitBtn3Click(Sender: TObject);
var
  bh,lbname:string;
begin
  bh:=e_id.Text;
  lbname:=e_name.text;
  if Length(e_id.Text)<2 then
    begin
     Application.MessageBox(PChar('编号不能为空或小于2位,请重新录入！')
      , PChar('提示'),MB_ICONEXCLAMATION);
      e_id.SetFocus();
      exit;
    end;
  if Bitbtn3.Tag=1 then
    begin
     try
      dm.ADO_lb.AppendRecord([bh,lbname]);
     except
     e_id.SetFocus;
     e_id.text:='';
     e_name.Text:='';
     mes:='录入错误！'+#13+#13+'注意:<编号>、<类别名>均不能为空'
     +#13+'     且不可重复,请重新录入！';
     application.messagebox(pchar(mes),pchar('提示'),MB_ICONEXCLAMATION);
     exit;
     end;
     dm.ADO_lb.Sort:='编号';
     e_id.text:='';
     e_name.Text:='';
     e_id.SetFocus();
    end
   else
    begin
    dm.ADO_lb.Edit;
    dm.ADO_lb.fieldbyname('编号').AsString:=bh;
    dm.ADO_lb.fieldbyname('类别').AsString:=lbname;
    try
     dm.ADO_lb.Post;
    except
     mes:='录入错误！'+#13+#13+'注意:<编号>、<类别名>均不能为空'
     +#13+'     且不可重复,请重新录入！';
     application.messagebox(pchar(mes),pchar('提示'),MB_ICONEXCLAMATION);
     dm.ADO_lb.Cancel;
     exit;
    end;
    dm.ADO_lb.Sort:='编号';
   end;
end;

procedure Tcfrm_lb.BitBtn4Click(Sender: TObject);
begin
dm.ADO_vcd.Open;
  if dm.ADO_vcd.Locate('小类',e_name.Text,[])=true then
   begin
    application.messagebox(pchar('此类别已经使用，不可删除！')
    ,pchar('提示'),MB_ICONEXCLAMATION);
    exit;
   end;
  dm.ADO_vcd.Close;
 mes:='是否要删除类别<'+dm.ADO_lb.fieldbyname('类别').AsString
       +'>';
 if application.MessageBox(pchar(mes),pchar('等待确认')
    ,+MB_ICONQUESTION+mb_okcancel)=idok then
    dm.ADO_lb.Delete;
end;

procedure Tcfrm_lb.FormClose(Sender: TObject; var Action: TCloseAction);
begin
 dm.ADO_lb.Close;
  release;
end;

end.