Delphi 7 - only enter an InputBox in an integer?

Question

Using Delphi 7, do you still need to force an input field that allows you to enter only numbers from 0 to 100?

Thanks!

Answer 1

You can easily write your own "super dialogue", for example,

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; 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.Text := Value; 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.Text := IntToStr(value); edt.OnChange := ValidateInput; result := frm.ShowModal = mrOK; if result then Value := StrToInt(edt.Text); finally frm.Free; end; end; 

This dialog allows you to enter both text and integers:

 v := 55; if TMultiInputBox.NumInputBox(Self, 'This is the title', 'Enter a number between 1 and 100:', 1, 100, v) then ShowMessage(IntToStr(v)); 

or

 s := 'Test'; if TMultiInputBox.TextInputBox(Self, 'This is the title', 'Enter some text:', s) then ShowMessage(s); 

Update

The commentator noted that class procedures (etc.) have not yet been introduced in Delphi 7. If so (I don’t remember ...), just remove all this syntactic sugar:

 var frm: TForm; lbl: TLabel; edt: TEdit; btnOK, btnCancel: TButton; shp: TShape; FMin, FMax: integer; FTitle, FText: string; procedure 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; function 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.Text := Value; result := frm.ShowModal = mrOK; if result then Value := edt.Text; finally frm.Free; end; end; type TInputValidator = class procedure ValidateInput(Sender: TObject); end; procedure TInputValidator.ValidateInput(Sender: TObject); var n: integer; begin btnOK.Enabled := TryStrToInt(edt.Text, n) and InRange(n, FMin, FMax); end; function NumInputBox(AOwner: TCustomForm; const ATitle, AText: string; AMin, AMax: integer; var Value: integer): boolean; var iv: TInputValidator; begin FMin := AMin; FMax := AMax; FTitle := ATitle; FText := AText; frm := TForm.Create(AOwner); try SetupDialog; edt.Text := IntToStr(value); iv := TInputValidator.Create; try edt.OnChange := iv.ValidateInput; result := frm.ShowModal = mrOK; if result then Value := StrToInt(edt.Text); finally iv.Free; end; finally frm.Free; end; end; 

Update 2

I wrote a new and much more enjoyable version of the dialogue. Now it looks exactly like the task dialog (I followed Microsoft's recommendations in detail), and offers many options for converting (for example, upper or lower case) and checking (many options) for input. It also adds an up and down control in case of integer input (it is not necessary to use natural numbers for this).

Source:

 unit MultiInput; interface uses Windows, SysUtils, Types, Controls, Graphics, Forms, StdCtrls, ExtCtrls, CommCtrl; type TAllowOnlyOption = (aoCapitalAZ, aoSmallAZ, aoAZ, aoLetters, aoDigits, aoSpace, aoPeriod, aoComma, aoSemicolon, aoHyphenMinus, aoPlus, aoUnderscore, aoAsterisk); TAllowOnlyOptions = set of TAllowOnlyOption; TInputVerifierFunc = reference to function(const S: string): boolean; TMultiInputBox = class strict private class var frm: TForm; edt: TEdit; btnOK, btnCancel: TButton; FMin, FMax: integer; FFloatMin, FFloatMax: real; FAllowEmptyString: boolean; FAllowOnly: TAllowOnlyOptions; FInputVerifierFunc: TInputVerifierFunc; spin: HWND; FTitle, FText: string; lineat: integer; R: TRect; class procedure Paint(Sender: TObject); class procedure FormActivate(Sender: TObject); class procedure SetupDialog; class procedure ValidateIntInput(Sender: TObject); class procedure ValidateRealInput(Sender: TObject); class procedure ValidateStrInput(Sender: TObject); private class procedure ValidateStrInputManual(Sender: TObject); public class function TextInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: string; ACharCase: TEditCharCase = ecNormal; AAllowEmptyString: boolean = true; AAllowOnly: TAllowOnlyOptions = []): boolean; class function CharInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: char; ACharCase: TEditCharCase = ecNormal; AAllowOnly: TAllowOnlyOptions = []): boolean; class function TextInputBoxEx(AOwner: TCustomForm; const ATitle, AText: string; var Value: string; ACharCase: TEditCharCase = ecNormal; AInputVerifierFunc: TInputVerifierFunc = nil): boolean; class function NumInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: integer; AMin: integer = -MaxInt + 1; AMax: integer = MaxInt): boolean; class function FloatInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: real; AMin: real; AMax: real): boolean; end; implementation uses Math, Messages, Character; class procedure TMultiInputBox.Paint(Sender: TObject); begin with frm.Canvas do begin Pen.Style := psSolid; Pen.Width := 1; Pen.Color := $00DFDFDF; Brush.Style := bsSolid; Brush.Color := clWhite; FillRect(Rect(0, 0, frm.ClientWidth, lineat)); MoveTo(0, lineat); LineTo(frm.ClientWidth, lineat); DrawText(frm.Canvas.Handle, FText, Length(FText), R, DT_NOPREFIX or DT_WORDBREAK); end; end; class procedure TMultiInputBox.SetupDialog; begin { * = Metrics from } { https://msdn.microsoft.com/en-us/windows/desktop/dn742486 } { and } { https://msdn.microsoft.com/en-us/windows/desktop/dn742478 } frm.Font.Name := 'Segoe UI'; frm.Font.Size := 9{*}; frm.Caption := FTitle; frm.Width := 400; frm.Position := poOwnerFormCenter; frm.BorderStyle := bsDialog; frm.OnPaint := Paint; frm.OnActivate := FormActivate; frm.Canvas.Font.Size := 12; { 'MainInstruction' } frm.Canvas.Font.Color := $00993300; R := Rect(11{*}, 11{*}, frm.Width - 11{*}, 11{*} + 2); DrawText(frm.Canvas.Handle, FText, Length(FText), R, DT_CALCRECT or DT_NOPREFIX or DT_WORDBREAK); edt := TEdit.Create(frm); edt.Parent := frm; edt.Top := R.Bottom + 5{*}; edt.Left := 11{*}; edt.Width := frm.ClientWidth - 2*11{*}; lineat := edt.Top + edt.Height + 11{*}; btnOK := TButton.Create(frm); btnOK.Parent := frm; btnOK.Height := 23{*}; btnOK.Default := true; btnOK.Caption := 'OK'; btnOK.ModalResult := mrOk; btnCancel := TButton.Create(frm); btnCancel.Parent := frm; btnCancel.Height := 23{*}; btnCancel.Cancel := true; btnCancel.Caption := 'Cancel'; btnCancel.ModalResult := mrCancel; btnCancel.Top := edt.Top + edt.Height + 11{*} + 1{*} + 11{*}; btnCancel.Left := frm.ClientWidth - btnCancel.Width - 11{*}; btnOK.Top := btnCancel.Top; btnOK.Left := btnCancel.Left - btnOK.Width - 7{*}; frm.ClientHeight := btnOK.Top + btnOK.Height + 11{*}; end; class procedure TMultiInputBox.ValidateStrInputManual(Sender: TObject); begin btnOK.Enabled := (not Assigned(FInputVerifierFunc)) or FInputVerifierFunc(edt.Text); end; class function TMultiInputBox.TextInputBoxEx(AOwner: TCustomForm; const ATitle, AText: string; var Value: string; ACharCase: TEditCharCase; AInputVerifierFunc: TInputVerifierFunc): boolean; begin FTitle := ATitle; FText := AText; FInputVerifierFunc := AInputVerifierFunc; frm := TForm.Create(AOwner); try SetupDialog; edt.Text := Value; edt.CharCase := ACharCase; edt.OnChange := ValidateStrInputManual; ValidateStrInputManual(nil); result := frm.ShowModal = mrOK; if result then Value := edt.Text; finally frm.Free; end; end; class procedure TMultiInputBox.ValidateStrInput(Sender: TObject); function IsValidStr: boolean; var S: string; i: integer; begin S := edt.Text; result := (Length(S) > 0) or FAllowEmptyString; if not result then Exit; if FAllowOnly = [] then Exit; if aoLetters in FAllowOnly then Include(FAllowOnly, aoAZ); if aoAZ in FAllowOnly then begin Include(FAllowOnly, aoCapitalAZ); Include(FAllowOnly, aoSmallAZ); end; result := true; for i := 1 to Length(S) do case S[i] of 'a'..'z': if not (aoSmallAZ in FAllowOnly) then Exit(false); 'A'..'Z': if not (aoCapitalAZ in FAllowOnly) then Exit(false); '0'..'9': if not (aoDigits in FAllowOnly) then Exit(false); ' ': if not (aoSpace in FAllowOnly) then Exit(false); '.': if not (aoPeriod in FAllowOnly) then Exit(false); ',': if not (aoComma in FAllowOnly) then Exit(false); ';': if not (aoSemicolon in FAllowOnly) then Exit(false); '-': if not (aoHyphenMinus in FAllowOnly) then Exit(false); '+': if not (aoPlus in FAllowOnly) then Exit(false); '_': if not (aoUnderscore in FAllowOnly) then Exit(false); '*': if not (aoAsterisk in FAllowOnly) then Exit(false); else if not (TCharacter.IsLetter(S[i]) and (aoLetters in FAllowOnly)) then Exit(false); end; end; begin btnOK.Enabled := IsValidStr; end; class function TMultiInputBox.TextInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: string; ACharCase: TEditCharCase = ecNormal; AAllowEmptyString: boolean = true; AAllowOnly: TAllowOnlyOptions = []): boolean; begin FTitle := ATitle; FText := AText; FAllowEmptyString := AAllowEmptyString; FAllowOnly := AAllowOnly; frm := TForm.Create(AOwner); try SetupDialog; edt.Text := Value; edt.CharCase := ACharCase; edt.OnChange := ValidateStrInput; ValidateStrInput(nil); result := frm.ShowModal = mrOK; if result then Value := edt.Text; finally frm.Free; end; end; class procedure TMultiInputBox.ValidateIntInput(Sender: TObject); var n: integer; begin btnOK.Enabled := TryStrToInt(edt.Text, n) and InRange(n, FMin, FMax); end; class procedure TMultiInputBox.ValidateRealInput(Sender: TObject); var x: double; begin btnOK.Enabled := TryStrToFloat(edt.Text, x) and InRange(x, FFloatMin, FFloatMax); end; class function TMultiInputBox.CharInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: char; ACharCase: TEditCharCase; AAllowOnly: TAllowOnlyOptions): boolean; begin FTitle := ATitle; FText := AText; FAllowEmptyString := false; FAllowOnly := AAllowOnly; frm := TForm.Create(AOwner); try SetupDialog; edt.Text := Value; edt.CharCase := ACharCase; edt.OnChange := ValidateStrInput; edt.MaxLength := 1; ValidateStrInput(nil); result := frm.ShowModal = mrOK; if result then Value := edt.Text[1]; finally frm.Free; end; end; class function TMultiInputBox.FloatInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: real; AMin, AMax: real): boolean; begin FFloatMin := AMin; FFloatMax := AMax; FTitle := ATitle; FText := AText; frm := TForm.Create(AOwner); try SetupDialog; edt.Text := FloatToStr(Value); edt.OnChange := ValidateRealInput; ValidateRealInput(nil); result := frm.ShowModal = mrOK; if result then Value := StrToFloat(edt.Text); finally frm.Free; end; end; class procedure TMultiInputBox.FormActivate(Sender: TObject); var b: boolean; begin if SystemParametersInfo(SPI_GETSNAPTODEFBUTTON, 0, @b, 0) and b then with btnOK do with ClientToScreen(Point(Width div 2, Height div 2)) do SetCursorPos(x, y); frm.OnActivate := nil; end; class function TMultiInputBox.NumInputBox(AOwner: TCustomForm; const ATitle, AText: string; var Value: integer; AMin: integer = -MaxInt + 1; AMax: integer = MaxInt): boolean; const UDM_SETPOS32 = WM_USER + 113; var ICCX: TInitCommonControlsEx; begin FMin := AMin; FMax := AMax; FTitle := ATitle; FText := AText; frm := TForm.Create(AOwner); try SetupDialog; ICCX.dwSize := sizeof(ICCX); ICCX.dwICC := ICC_UPDOWN_CLASS; InitCommonControlsEx(ICCX); spin := CreateWindowEx(0, PChar(UPDOWN_CLASS), nil, WS_CHILDWINDOW or WS_VISIBLE or UDS_NOTHOUSANDS or UDS_SETBUDDYINT or UDS_ALIGNRIGHT or UDS_ARROWKEYS or UDS_HOTTRACK, 0, 0, 0, 0, frm.Handle, 0, HInstance, nil); SendMessage(spin, UDM_SETRANGE32, FMin, FMax); SendMessage(spin, UDM_SETPOS32, 0, Value); SendMessage(spin, UDM_SETBUDDY, edt.Handle, 0); if FMin >= 0 then edt.NumbersOnly := true; edt.Text := IntToStr(value); edt.OnChange := ValidateIntInput; ValidateIntInput(nil); result := frm.ShowModal = mrOK; if result then Value := StrToInt(edt.Text); finally frm.Free; end; end; end. 

Full documentation (and source code) will always be found at https://specials.rejbrand.se/dev/classes/multiinput/readme.html .

Answer 2

you can allow the user to enter only numbers in the input field by adding the value ES_NUMBER to the TEdit style inside the input window.

check this sample.

 const InputBoxNumberMessage = WM_USER + 666;// a custom message type TForm1 = class(TForm) Button1: TButton; procedure Button1Click(Sender: TObject); private procedure InputBoxSetOnlyNumbers(var Msg: TMessage); message InputBoxNumberMessage; public end; var Form1: TForm1; implementation {$R *.dfm} procedure TForm1.Button1Click(Sender: TObject); var InputString: string; begin PostMessage(Handle, InputBoxNumberMessage, 0, 0); InputString := InputBox('Input', 'Enter a number', ''); ShowMessage(InputString); end; procedure TForm1.InputBoxSetOnlyNumbers(var Msg: TMessage); var hActiveForm : HWND; hEdit : HWND; dwLong : Longint; begin hActiveForm := Screen.ActiveForm.Handle; if (hActiveForm <> 0) then begin hEdit := FindWindowEx(hActiveForm, 0, 'TEdit', nil);//determine the handle of the TEdit dwLong := GetWindowLong(hEdit, GWL_STYLE);//get the current style of the control SetWindowLong(hEdit, GWL_STYLE, dwLong or ES_NUMBER)//set the new style end; end; 

Note : unfortunately, this method does not allow checking the range of numbers.

Answer 3

You can use InputQuery from the QDialogs module, which has an overloaded version with Min and Max parameters to limit the input range of Integer. Something like that:

 var i:Integer; begin i:=0; // Initial value to show the user in the textbox if InputQuery('Dialog Caption', 'Please enter the number between 0 and 100:', i, 0, 100) then ShowMessage('Entered: '+IntToStr(i)); end; 

Remember to add QDialogs to the use clause, otherwise this version of the function will not be found.

BUT this dialog will not prevent the user from entering a value that is beyond the scope; he will quietly "cut" him to the nearest border. For example, if the user enters -20, the variable "i" will be set to 0. And if he goes into 200, "i" will be set to 100. I'm not sure if this functionality will suit everyone, but this is one way to achieve this without typing any custom code. Hope this helps.

Answer 4

This work with D6. The TryStrToInt function is from SysUtils.

 procedure TForm.ButtonClick(Sender: TObject); var vInt:Integer; vStr:String; begin Repeat Repeat vStr:=InputBox('Some title','Enter integer betwen 0-100',''); Until TryStrToInt(vStr, vInt); Until (vInt>=0) and (vInt<=100); end; 

Answer 5

No, there is no way to do this. You must write your own dialog that checks the input for the edit control.