盒子论坛 v2.1

unit login;

interface

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

type
  Tloginform = class(TForm)
    Panel1: TPanel;
    Label1: TLabel;
    Label2: TLabel;
    username: TComboBox;
    password: TEdit;
    btnok: TButton;
    btncancel: TButton;
    DataSource1: TDataSource;
    ADOConnection1: TADOConnection;
    ADOQuery_login: TADOQuery;
    procedure btnokClick(Sender: TObject);
    procedure btncancelClick(Sender: TObject);
    procedure usernameDropDown(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  loginform: Tloginform;

implementation
uses main;
{$R *.dfm}
var
itimes:integer=0;

procedure Tloginform.usernameDropDown(Sender: TObject);
var
i:integer;
begin
// 当用户选择已经存在的或用户可以输入数据
username.Clear;
with ADOQuery_login do
begin
  close;
  sql.Clear;
  sql.Add('select * from psw');
  open;
  if recordcount>0 then
  begin
    first;
    for i:=0 to recordcount-1 do
    begin
    username.Items.Add(fieldbyname('用户名').AsString);
    next;
    end;
  end
  else
   showmessage('当前没有用户。请原谅'); //当前没有记录就不能对数据进行操作
end;
end;

procedure Tloginform.btnokClick(Sender: TObject);
var
mima,mingzi:string;
begin
mima:=username.Text; // 用户名
mingzi:=password.Text; //密码
inc(itimes);
if username.Items.Count>0 then
begin
   username.ItemIndex:=0;
   with ADOQuery_login do
     begin
       // 当用户名与密码正确并且输入次数少于三次时就登录成功
       if locate('用户名',mingzi,[lopartialkey]) and locate('密码',mima,[lopartialkey]) and (itimes<4) then
        begin
          close;
          sql.Clear;
          sql.Add('select * from psw where 用户名='''+mingzi+''''+' and  密码='''+mima+'''');
          open;
          application.CreateForm(TmainForm,mainform);
          //mainform.StatusBar1.Panels.Items[1].Text:=name;
          //mainform.StatusBar1.Panels.Items[3].Text:=fieldbyname('权限').AsString;
        if fieldbyname('权限').AsString='操作员' then
            begin
                with mainform do
                begin
                N12.Enabled:=false;
                N13.Enabled:=false;
                N14.Enabled:=false;
                end
            end;
          loginform.Hide;
          loginform.Free;
          mainform.ShowModal;
          mainform.Free;
        end
       else
       begin
         if MessageDlg('密码错误，请重新输入',mtConfirmation, [mbYes, mbNo],0)=mrYes then
           begin
            username.Clear;
            username.SetFocus;
           end
           else
             close;
       end;
       if itimes>3 then
         begin
          showmessage('很抱歉。你没有权力使用本系统');
          application.Terminate;
         end;
     end;
  end
else
showmessage('数据库没有用户名');
end;

procedure Tloginform.btncancelClick(Sender: TObject);
begin
application.Terminate;
end;

end.

--------------------------------------------------

unit main;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, ComCtrls, Menus;

type
  Tmainform = class(TForm)
    MainMenu1: TMainMenu;
    N1: TMenuItem;
    N2: TMenuItem;
    N3: TMenuItem;
    N5: TMenuItem;
    N6: TMenuItem;
    N7: TMenuItem;
    N8: TMenuItem;
    N9: TMenuItem;
    N10: TMenuItem;
    N11: TMenuItem;
    N12: TMenuItem;
    N13: TMenuItem;
    N14: TMenuItem;
    N15: TMenuItem;
    StatusBar1: TStatusBar;
    N4: TMenuItem;
    //procedure Exit1Click(Sender: TObject);
    procedure N4Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  mainform: Tmainform;

implementation

{$R *.dfm}

//procedure Tmainform.Exit1Click(Sender: TObject);
//begin
//close;
//end;

procedure Tmainform.N4Click(Sender: TObject);
begin
application.Terminate;
end;

end.

就是在
procedure Tmainform.N4Click(Sender: TObject);
begin
application.Terminate;
end;
退出时报
"abstract.error"

请帮帮我吧！~~~~~

----------------------------------------------
-

作者：

sephil (NAILY Soft)	★☆☆☆☆	-
	盒子中级会员

2004/5/3 7:20:46

3楼：

问题应该不是出在这里
可能是其他的地方有问题

abstract error是因为你使用了某个类里的纯虚函数
----------------------------------------------
Copyright 2008 ? NAILY Soft

Click here to redirect to my home
Click here to redirect to my blog

信息

登陆以后才能回复