login.pas

delphi下 数据库图书馆管理系统的实现

unit login;

interface

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

type
  TLoginForm = class(TForm)
    GroupBox1: TGroupBox;
    Image1: TImage;
    LabelYongHu: TLabel;
    LabelTiShi: TLabel;
    LabelPassWord: TLabel;
    EditUser: TEdit;
    EditPassWord: TEdit;
    ButtonCancel: TButton;
    Button1: TButton;
    TableYonghu: TTable;
    procedure Button1Click(Sender: TObject);
    procedure ButtonCancelClick(Sender: TObject);
    procedure FormShow(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  LoginForm: TLoginForm;
  TimeID:Integer;
  QuanXian:String;

implementation
uses DataModule, Main;

{$R *.dfm}

procedure TLoginForm.Button1Click(Sender: TObject);
begin
    tableyonghu.DatabaseName:=DataModule1.Database1.DatabaseName;
    TimeID:=TimeID+1;
    tableyonghu.Open;
    TableYongHu.SetKey;
    TableYongHu.FieldByName('YONGHU').AsString:=EditUser.Text;
    TableYongHu.GotoKey;
    If (EditUser.Text=TableYongHu.FieldByName('YONGHU').AsString) And (EditPassWord.Text=TableYongHu.FieldByName('KOULING').AsString) Then
        Begin
           ModalResult:=mrOK;
           QuanXian:=TableYongHu.FieldByName('QUANXIAN').AsString;
        End
     Else
         Begin
             If TimeID>3 Then
                 Begin
                     Application.Terminate;
                 End
              Else If EditUser.Text <> TableYongHu.FieldByName('YONGHU').AsString Then
                  Begin
                      Application.MessageBox('非法用户，请您输入正确的用户名！','用户名',MB_OK+MB_ICONEXCLAMATION);
                      EditUser.SetFocus;
                  End
              Else
                  Begin
                      Application.MessageBox('输入密码错误，请再输入一次','密码',MB_OK+MB_ICONEXCLAMATION);
                      EditPassWord.SetFocus;
                  End;
         End;
    if quanxian='system' then ;

    if quanxian='operator' then
        begin
            Mainform.O1.Visible:=false
        end
    else if quanxian='user' then
        begin
            Mainform.D1.Visible:=false;
            Mainform.D2.Visible:=false;
            Mainform.L1.Visible:=false;
            Mainform.G1.Visible:=false;
            Mainform.P1.Visible:=false;
            Mainform.O1.Visible:=false;
        end
    else if quanxian='' then
        begin
            Mainform.D1.Visible:=false;
            Mainform.D2.Visible:=false;
            Mainform.L1.Visible:=false;
            Mainform.G1.Visible:=false;
            Mainform.P1.Visible:=false;
            Mainform.O1.Visible:=false;
            Mainform.S1.Visible:=false;
            Mainform.W1.Visible:=false;
        end;
end;

procedure TLoginForm.ButtonCancelClick(Sender: TObject);
begin
    Application.Terminate;
end;

procedure TLoginForm.FormShow(Sender: TObject);
begin
    TimeID:=0;
end;

end.