Blank im Edit-Control für Integer/Float-Werte

[ichbins]

Hallo, willkommen in der Delphi-Praxis!


was meinst du mit Blank? Ein Leerzeichen? Wo liegt denn dann das Problem?

wenn du eine Edit-Komponente mit Sonderfunktionen schreiben willst, kannst du dich an diesem Code orientieren (Edit zum Eingeben eines Geldbetrags):

Delphi-Quellcode:

unit MyMoneyEdit;

interface

uses
  SysUtils, Classes, Controls, StdCtrls;

type
  TMoneyEdit = class(TEdit)
  private
    { Private-Deklarationen }
    reactonc:boolean;
  protected
    { Protected-Deklarationen }
    procedure setmoney(money:real);
    function getmoney:real;
  public
    { Public-Deklarationen }
  published
    { Published-Deklarationen }
    procedure keypress(var key:char); override;
    property money:real read getmoney write setmoney;
    procedure change; override;
    constructor create(aOwner:tcomponent); override;
  end;

procedure Register;

implementation

procedure Register;
begin
  RegisterComponents('Beispiele', [TMoneyEdit]);
end;

constructor tmoneyedit.create(aOwner:tcomponent);
begin
  inherited create(aOwner);
  reactonc:=true;
end;

procedure tmoneyedit.setmoney(money:real);
begin
  if not (((text='') or (text='-')) and (money=0)) then
    self.text:=floattostr(money);
end;

function tmoneyedit.getmoney:real;
begin
  if (text='') or (text='-') then
    result:=0
  else
    try
      result:=strtofloat(text);
    except
      result:=0;
      text:='';
    end;
end;

procedure tmoneyedit.Change;
var
  curpos,i,commavalues:integer;
  commaexists:boolean;
  s:string;
begin
  if not reactonc then
    exit;
  reactonc:=false;
  curpos:=self.GetSelStart;
  if not((text='') or (text='-') or (text[length(text)]=',')) then
  begin
    commaexists:=false;
    commavalues:=0;
    for i:=1 to length(text) do
    begin
      if commaexists then
        inc(commavalues);
      if commavalues>2 then
      begin
        s:=text;
        delete(s,i,length(text));
        text:=s;
        break;
      end;
      if text[i]=',' then
      begin
        if commaexists then
        begin
          s:=text;
          delete(s,i,length(text));
          text:=s;
          break;
        end;
        commaexists:=true;
      end;
    end;
  end;
  setselstart(curpos);
  reactonc:=true;
  inherited change;
end;

procedure tmoneyedit.KeyPress(var key:char);
begin
  if Key = '.' then Key := ',';
  If not (Key in [#43..#45, #48..#57, #8, #13]) then
    Key := #0;
  If (Pos(',', Text) <> 0) then
    if Key = ',' then
      Key := #0;
  inherited keypress(key);
end;

end.