login.pas

银行学生助学贷款管理系统 随着社会的进步

unit login;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, Buttons, ExtCtrls, jpeg,db, XPMenu, RxGIF;

type
  TLoginForm = class(TForm)
    Image1: TImage;
    Edit2: TEdit;
      Button1: TButton;
    Panel1: TPanel;
    ComboBox1: TComboBox;
    Panel2: TPanel;
    Edit1: TEdit;
    Panel3: TPanel;
    Label1: TLabel;
    Label2: TLabel;
    Button2: TButton;
    Button3: TButton;
    procedure ComboBox1DropDown(Sender: TObject);
    procedure BitBtn1Click(Sender: TObject);
    procedure BitBtn2Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure FormShow(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  LoginForm: TLoginForm;

implementation
uses md,main, Splash;
{$R *.dfm}
var
itimes:integer=0;
procedure TLoginForm.ComboBox1DropDown(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
combobox1.Clear;
with datamd.ADOquerymange do
begin
  close;
  sql.Clear;
  sql.Add('select * from manage');
  open;
  if recordcount>0 then
  begin
    first;
    for i:=0 to recordcount-1 do
    begin
    combobox1.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.BitBtn1Click(Sender: TObject);
var
password,username:string;
begin
username:=combobox1.Text; // 用户名
password:=edit1.Text; //密码
inc(itimes);

if password='' then
begin
ShowMessage('请输入密码');
exit;
end else
begin

if combobox1.Items.Count>0 then
begin
   combobox1.ItemIndex:=0;
   with datamd.ADOqueryMange 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
          close;
          sql.Clear;
          sql.Add('select * from manage where 用户名='''+username+'''');
          open;
          edit2.Text:=fieldbyname('密码').AsString;
          if  (edit1.Text= edit2.Text) and (itimes<4) then
          begin
          application.CreateForm(TmainForm,mainform);
          mainform.StatusBar1.Panels.Items[1].Text:=username;
          mainform.StatusBar1.Panels.Items[3].Text:=fieldbyname('权限').AsString;
          if fieldbyname('权限').AsString='操作员' then
            begin
                with mainform do
                begin
                ToolButton3.Enabled:=false;
                ToolButton7.Enabled:=false;
                ToolButton1.Enabled:=false;
                Mdfyitem.Enabled:=false;
                mdfname.Enabled:=false;
                AddUser.Enabled:=false;
                
                end
            end;
          loginform.Hide;
 //         loginform.Free;
          mainform.ShowModal;
          mainform.Free;
        end
       else
       begin
         if MessageDlg('密码密码，请重新输入',mtConfirmation, [mbYes, mbNo],0)=mrYes then
           begin
            edit1.Clear;
            edit1.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;
end;

procedure TLoginForm.BitBtn2Click(Sender: TObject);
begin
application.Terminate;
end;

procedure TLoginForm.Button1Click(Sender: TObject);
var
 username:string;
begin
   username:=ComboBox1.Text;
   with datamd.ADOqueryMange 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
          close;
          sql.Clear;
          sql.Add('select * from manage where 用户名='''+username+'''');
          open;
          edit2.Text:=fieldbyname('密码').AsString;
        end;
      end;


procedure TLoginForm.FormShow(Sender: TObject);
begin
//SplashForm.Free;
end;

end.