如何在编辑框中隐藏密码文本?

时间:2011-06-14 17:40:06

标签: delphi passwords

我有一个输入框,希望用户输入密码,但同时隐藏它。

这可能吗?

到目前为止,这是我的代码:

var password : string;
begin
 password := InputBox('Password: ', 'Please enter your password: ', password)
end;

6 个答案:

答案 0 :(得分:16)

你'不能'使用InputBox,因为,嗯......显然这个功能不会隐藏文字。

标准Windows编辑控件具有“密码模式”。要对此进行测试,只需在表单中添加TEdit并将其PasswordChar设置为*

如果你想在输入框中使用这样的编辑,你必须自己编写这个对话框,比如我的“超级输入对话框”:

type
  TMultiInputBox = class
  strict private
    class var
      frm: TForm;
      lbl: TLabel;
      edt: TEdit;
      btnOK,
      btnCancel: TButton;
      shp: TShape;
      FMin, FMax: integer;
      FTitle, FText: string;
    class procedure SetupDialog;
    class procedure ValidateInput(Sender: TObject);
  public
    class function TextInputBox(AOwner: TCustomForm; const ATitle,
      AText: string; var Value: string): boolean;
    class function NumInputBox(AOwner: TCustomForm; const ATitle,
      AText: string; AMin, AMax: integer; var Value: integer): boolean;
    class function PasswordInputBox(AOwner: TCustomForm; const ATitle,
      AText: string; var Value: string): boolean;
  end;

class procedure TMultiInputBox.SetupDialog;
begin
  frm.Caption := FTitle;
  frm.Width := 512;
  frm.Position := poOwnerFormCenter;
  frm.BorderStyle := bsDialog;
  lbl := TLabel.Create(frm);
  lbl.Parent := frm;
  lbl.Left := 8;
  lbl.Top := 8;
  lbl.Width := frm.ClientWidth - 16;
  lbl.Caption := FText;
  edt := TEdit.Create(frm);
  edt.Parent := frm;
  edt.Top := lbl.Top + lbl.Height + 8;
  edt.Left := 8;
  edt.Width := frm.ClientWidth - 16;
  btnOK := TButton.Create(frm);
  btnOK.Parent := frm;
  btnOK.Default := true;
  btnOK.Caption := 'OK';
  btnOK.ModalResult := mrOk;
  btnCancel := TButton.Create(frm);
  btnCancel.Parent := frm;
  btnCancel.Cancel := true;
  btnCancel.Caption := 'Cancel';
  btnCancel.ModalResult := mrCancel;
  btnCancel.Top := edt.Top + edt.Height + 16;
  btnCancel.Left := frm.ClientWidth - btnCancel.Width - 8;
  btnOK.Top := btnCancel.Top;
  btnOK.Left := btnCancel.Left - btnOK.Width - 4;
  frm.ClientHeight := btnOK.Top + btnOK.Height + 8;
  shp := TShape.Create(frm);
  shp.Parent := frm;
  shp.Brush.Color := clWhite;
  shp.Pen.Style := psClear;
  shp.Shape := stRectangle;
  shp.Align := alTop;
  shp.Height := btnOK.Top - 8;
  shp.SendToBack;
end;

class function TMultiInputBox.TextInputBox(AOwner: TCustomForm; const ATitle,
  AText: string; var Value: string): boolean;
begin
  FTitle := ATitle;
  FText := AText;

  frm := TForm.Create(AOwner);
  try
    SetupDialog;
    edt.NumbersOnly := false;
    edt.PasswordChar := #0;
    edt.Text := Value;
    edt.OnChange := nil;
    result := frm.ShowModal = mrOK;
    if result then Value := edt.Text;
  finally
    frm.Free;
  end;
end;

class function TMultiInputBox.PasswordInputBox(AOwner: TCustomForm;
  const ATitle, AText: string; var Value: string): boolean;
begin
  FTitle := ATitle;
  FText := AText;

  frm := TForm.Create(AOwner);
  try
    SetupDialog;
    edt.NumbersOnly := false;
    edt.PasswordChar := '*';
    edt.Text := Value;
    edt.OnChange := nil;
    result := frm.ShowModal = mrOK;
    if result then Value := edt.Text;
  finally
    frm.Free;
  end;
end;

class procedure TMultiInputBox.ValidateInput(Sender: TObject);
var
  n: integer;
begin
  btnOK.Enabled := TryStrToInt(edt.Text, n) and InRange(n, FMin, FMax);
end;

class function TMultiInputBox.NumInputBox(AOwner: TCustomForm; const ATitle,
  AText: string; AMin, AMax: integer; var Value: integer): boolean;
begin
  FMin := AMin;
  FMax := AMax;
  FTitle := ATitle;
  FText := AText;

  frm := TForm.Create(AOwner);
  try
    SetupDialog;
    edt.NumbersOnly := true;
    edt.PasswordChar := #0;
    edt.Text := IntToStr(value);
    edt.OnChange := ValidateInput;
    result := frm.ShowModal = mrOK;
    if result then Value := StrToInt(edt.Text);
  finally
    frm.Free;
  end;
end;

试一试:

procedure TForm1.Button1Click(Sender: TObject);
var
  str: string;
begin
  str := '';
  if TMultiInputBox.PasswordInputBox(Self, 'Password',
    'Please enter your password:', str) then
    ShowMessageFmt('You entered %s.', [str]);
end;

Screenshot http://privat.rejbrand.se/superinputdlgpsw.png

答案 1 :(得分:5)

这看起来像是在这里回答:

Delphi InputBox for password entry?

答案 2 :(得分:3)

不要使用InputBox。自己创建一个对话框,并确保将TEdit.PasswordChar设置为#0以外的其他内容。

也可以通过Windows消息获取InputBox的Edit控件的句柄并设置PasswordChar,但我不知道如何做到这一点(特别是因为InputBox是一个阻塞调用。)

Delphi XE在创建新表单时也可以使用Password Dialog表单。旧版本可能也是如此,XE恰好就是我现在正在运行的版本。 (编辑Delphi 2007也有它.2007& XE是我现在安装的唯一版本的Delphi,所以我无法验证任何其他版本。)

答案 3 :(得分:2)

const
  InputBoxMessage = WM_USER + 200;
type
  TForm1 = class(TForm)
  ...
    procedure InputBoxSetPasswordChar(var Msg: TMessage); message InputBoxMessage;
    function GetPassword: String;
  ...
  end;
...
procedure TForm1.InputBoxSetPasswordChar(var Msg: TMessage);
var
  hInputForm, hEdit: HWND;
begin
  hInputForm := Screen.Forms[0].Handle;
  if (hInputForm <> 0) then
  begin
    hEdit := FindWindowEx(hInputForm, 0, 'TEdit', nil);
    SendMessage(hEdit, EM_SETPASSWORDCHAR, Ord('*'), 0);
  end;
end;

function TForm1.GetPassword: String;
begin
  PostMessage(Handle, InputBoxMessage, 0, 0);
  Result := InputBox('Title', 'Password:', '');
end;

答案 4 :(得分:0)

我认为你还需要设置:

  Echomode := eemPassword

至少对于TdlcxLabeledDBTextEdit。

答案 5 :(得分:-1)

procedure TForm1.Edit1KeyUp(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
  if checkbox1.checked = true then
    edit1.passwordchar := '*'
   else
    edit1.PasswordChar := #0;
  end;
end;