floating point source code

unit Unit1;
interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  StdCtrls, Buttons, ExtCtrls;

type
  TForm1 = class(TForm)
    number: TEdit;
    bin: TStaticText;
    Label1: TLabel;
    singleBtn: TSpeedButton;
    doubleBtn: TSpeedButton;
    Label3: TLabel;
    GOBtn: TButton;
    clearBtn: TSpeedButton;
    Label2: TLabel;
    exponent: TStaticText;
    sign: TStaticText;
    StaticText1: TStaticText;
    coef: TStaticText;
    Label4: TLabel;
    Label5: TLabel;
    Label6: TLabel;
    Label7: TLabel;
    Label8: TLabel;
    Label9: TLabel;
    procedure FormCreate(Sender: TObject);
    procedure FormKeyPress(Sender: TObject; var Key: Char);
    procedure GOBtnClick(Sender: TObject);
    procedure clearBtnClick(Sender: TObject);
    procedure singleBtnClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

type TA = array[0..7] of byte;
     PA = ^TA;

const kbfilter = ['0'..'9',#8,'.','-'];
      msg71 = 'E=[E7..E0]';
      msg72 = 'E=[E10..E0]';
      msg81 = 'M=[M1..M23]';
      msg82 = 'M=[M1..M52]';
      msg91 = 'value = (-1)^S*(1.M)*2^(E-127)';
      msg92 = 'value = (-1)^S*(1.M)*2^(E-1023)';

procedure TForm1.FormCreate(Sender: TObject);
begin
 decimalseparator := '.';
 label7.Caption := msg71;
 label8.Caption:= msg81;
 label9.Caption := msg91;
end;

procedure cleartext;
begin
 with form1 do
  begin
   bin.caption := '';
   sign.Caption := '';
   exponent.Caption := '';
   coef.caption := '';
  end;
end;

procedure TForm1.FormKeyPress(Sender: TObject; var Key: Char);
begin
 if activecontrol = number then
  begin
   if key in kbfilter then
    begin
     if key = '.'  then
      if pos(key,number.text) > 0 then key := #0;
    end
   else key := #0;
  end;
end;

procedure TForm1.GOBtnClick(Sender: TObject);
//show format
var p : PA;
    i,j : byte;
    s,t : string;
    f32 : single;
    f64 : double;
begin
 s := '';
 cleartext;
 try
  if singleBtn.Down then
   begin
    f32 := strtofloat(form1.number.text);
    p := PA(@f32);
    for j := 3 downto 0 do
     for i := 7 downto 0 do s := s + chr(((p^[j] shr i) and 1) + ord('0'));
    sign.Caption := s[1];
    t := '';
    for i := 2 to 9 do t := t + s[i];
    exponent.Caption := t;
    t := '';
    for i := 10 to 32 do t := t + s[i];
    coef.Caption := t;
   end
   else
    begin
     f64 := strtofloat(number.Text);
     p := PA(@f64);
     for j := 7 downto 0 do
      for i := 7 downto 0 do s := s + chr(((p^[j] shr i) and 1) + ord('0'));
    sign.Caption := s[1];
    t := '';
    for i := 2 to 12 do t := t + s[i];
    exponent.Caption := t;
    t := '';
    for i := 13 to 64 do t := t + s[i];
    coef.Caption := t;
   end;
  bin.Caption := s;
 except
  bin.caption := 'format error';
 end;
end;

procedure TForm1.clearBtnClick(Sender: TObject);
begin
 cleartext;
 number.text := '';
end;

procedure TForm1.singleBtnClick(Sender: TObject);
begin
 cleartext;
 if singleBtn.Down then
  begin
   label7.Caption := msg71;
   label8.Caption:= msg81;
   label9.Caption := msg91;
  end
  else
   begin
    label7.Caption := msg72;
    label8.Caption:= msg82;
    label9.Caption := msg92;
   end;
end;

end.