delphi中登录窗体完美实现办法

工程文件 program stuResult; uses Forms, controls, login in 'login.pas' {loginform}, MainFrm in 'MainFrm.pas' {mainform}, resultFrm in 'resultFrm.pas' {resultform}, dmFrm in 'dmFrm.pas' {DM: TDataModule}, termAdd in 'termAdd.pas' {termForm}, classAdd in 'classAdd.pas' {classForm}, courseAdd in 'courseAdd.pas' {courseForm}, specialFrm in 'specialFrm.pas' {specialForm}, specialBrowseFrm in 'specialBrowseFrm.pas' {specialBrowseForm}, specialModifyFrm in 'specialModifyFrm.pas' {specialModifyForm}, studentFrm in 'studentFrm.pas' {studentForm}, userfrm in 'userfrm.pas' {userForm}, about in 'about.pas' {AboutBox}, sysSetFrm in 'sysSetFrm.pas' {sysSetForm}; {$R *.res} begin Application.Initialize; Application.CreateForm(TDM, DM); Application.CreateForm(Tmainform, mainform); //主窗体MDI和登录窗体fsNormal的visible属性为false loginform:=Tloginform.Create(Application); loginform.ShowModal; application.Run; end. 登录窗体 procedure Tloginform.Button1Click(Sender: TObject); begin DM.ADOQuery1.Close; DM.ADOQuery1.SQL.Clear; DM.ADOQuery1.SQL.Text:='Select * From tbUser where 用户名='''+Edit1.Text+''' and 密码='''+edit2.Text+''''; DM.ADOQuery1.Open; if DM.ADOQuery1.Bof and DM.ADOQuery1.Eof then begin Application.MessageBox('用户名或密码错误','出错',0+48); Edit1.SetFocus; Edit1.SelectAll; end else begin mainform.Show; loginform.Hide; loginform.FreeOnRelease; end; end;