pfm_userpass.pas

主要是介绍DELPHI三层应用以及分布式数据库的应用

unit pfm_userpass;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  StdCtrls, Db, DBTables, Grids, DBGrids, ExtCtrls, DBCtrls, Buttons, Mask;

type
  Tfm_userpass = class(TForm)
    GroupBox1: TGroupBox;
    Query1: TQuery;
    Label1: TLabel;
    BitBtn1: TBitBtn;
    DBGrid1: TDBGrid;
    DataSource1: TDataSource;
    DBEdit1: TDBEdit;
    BitBtn2: TBitBtn;
    BitBtn3: TBitBtn;
    Label3: TLabel;
    DBEdit3: TDBEdit;
    Button1: TButton;
    Label2: TLabel;
    Button2: TButton;
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
    procedure Query1BeforePost(DataSet: TDataSet);
    procedure BitBtn3Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  fm_userpass: Tfm_userpass;

implementation

{$R *.DFM}

procedure Tfm_userpass.BitBtn1Click(Sender: TObject);
begin
    query1.Insert;
    bitbtn3.Enabled :=false;
    dbedit1.Enabled :=true;
    dbedit3.Enabled :=true;
    button2.Enabled :=true;
    
    dbedit1.SetFocus ;
end;

procedure Tfm_userpass.BitBtn2Click(Sender: TObject);
begin
    if (query1.State=dsinsert) or (query1.state=dsedit) then
    begin
        query1.Post;
        dbedit1.Enabled :=false;
        dbedit3.Enabled :=false;
         bitbtn3.Enabled :=true;
        button2.Enabled :=false;
        //query1.active:=false;
        //query1.active:=true;
    end;
end;

procedure Tfm_userpass.Query1BeforePost(DataSet: TDataSet);
begin
    if length(query1.FieldByName('username').asstring)<4 then
    begin
        showmessage('帐号要4~8位');
        abort;
        exit;
    end;
    
end;

procedure Tfm_userpass.BitBtn3Click(Sender: TObject);
begin
    if dbedit1.Text <>'admin' then
    query1.Delete
    else
    showmessage('管理员帐号不能删除');
end;

procedure Tfm_userpass.Button1Click(Sender: TObject);
begin
close;
end;

procedure Tfm_userpass.Button2Click(Sender: TObject);
begin
        dbedit1.Enabled :=false;
        dbedit3.Enabled :=false;
        button2.Enabled :=false;
         bitbtn3.Enabled :=true;
        

        query1.Cancel;

end;

end.