Code:

unit CurrEdit;

interface

uses

SysUtils,

WinTypes,

WinProcs,

Messages,

Classes,

Graphics,

Controls,

Menus,

Forms,

Dialogs,

StdCtrls;

type

TCurrencyEdit = class(TCustomMemo)

private

   DispFormat: string;

   FieldValue: Extended;

   procedure SetFormat(A: string);

   procedure SetFieldValue(A: Extended);

   procedure CMEnter(var Message: TCMEnter); message CM_ENTER;

   procedure CMExit(var Message: TCMExit); message CM_EXIT;

   procedure FormatText;

   procedure UnFormatText;

protected

   procedure KeyPress(var Key: Char); override;

   procedure CreateParams(var Params: TCreateParams); override;

public

   constructor Create(AOwner: TComponent); override;

published

   property Alignment default taRightJustify;

   property AutoSize default True;

   property BorderStyle;

   property Color;

   property Ctl3D;

   property DisplayFormat: string read DispFormat write SetFormat;

   property DragCursor;

   property DragMode;

   property Enabled;

   property Font;

   property HideSelection;

   property MaxLength;

   property ParentColor;

   property ParentCtl3D;

   property ParentFont;

   property ParentShowHint;

   property PopupMenu;

   property ReadOnly;

   property ShowHint;

   property TabOrder;

   property Value: Extended read FieldValue write SetFieldValue;

   property Visible;

   property OnChange;

   property OnClick;

   property OnDblClick;

   property OnDragDrop;

   property OnDragOver;

   property OnEndDrag;

   property OnEnter;

   property OnExit;

   property OnKeyDown;

   property OnKeyPress;

   property OnKeyUp;

   property OnMouseDown;

   property OnMouseMove;

   property OnMouseUp;

end;

procedure Register;

implementation

procedure Register;

begin

RegisterComponents('Additional', [TCurrencyEdit]);

end;

constructor TCurrencyEdit.Create(AOwner: TComponent);

begin

inherited Create(AOwner);

AutoSize := True;

Alignment := taRightJustify;

Width := 121;

Height := 25;

DispFormat := '$,0.00;($,0.00)';

FieldValue := 0.0;

AutoSelect := False;

WantReturns := False;

WordWrap := False;

FormatText;

end;

procedure TCurrencyEdit.SetFormat(A: string);

begin

if DispFormat <> A then

begin

   DispFormat := A;

   FormatText;

end;

end;

procedure TCurrencyEdit.SetFieldValue(A: Extended);

begin

if FieldValue <> A then

begin

   FieldValue := A;

   FormatText;

end;

end;

procedure TCurrencyEdit.UnFormatText;

var

TmpText: string;

Tmp: Byte;

IsNeg: Boolean;

begin

IsNeg := (Pos('-', Text) > 0) or (Pos('(', Text) > 0);

TmpText := '';

for Tmp := 1 to Length(Text) do

   if Text[Tmp] in ['0'..'9', '.'] then

     TmpText := TmpText + Text[Tmp];

try

   FieldValue := StrToFloat(TmpText);

   if IsNeg then

     FieldValue := -FieldValue;

except

   MessageBeep(mb_IconAsterisk);

end;

end;

procedure TCurrencyEdit.FormatText;

begin

Text := FormatFloat(DispFormat, FieldValue);

end;

procedure TCurrencyEdit.CMEnter(var Message: TCMEnter);

begin

SelectAll;

inherited;

end;

procedure TCurrencyEdit.CMExit(var Message: TCMExit);

begin

UnformatText;

FormatText;

inherited;

end;

procedure TCurrencyEdit.KeyPress(var Key: Char);

begin

if not (Key in ['0'..'9', '.', '-']) then

   Key := #0;

inherited KeyPress(Key);

end;

procedure TCurrencyEdit.CreateParams(var Params: TCreateParams);

begin

inherited CreateParams(Params);

case Alignment of

   taLeftJustify: Params.Style := Params.Style or ES_LEFT and not ES_MULTILINE;

   taRightJustify: Params.Style := Params.Style or ES_RIGHT and not

     ES_MULTILINE;

   taCenter: Params.Style := Params.Style or ES_CENTER and not ES_MULTILINE;

end;

end;

end.