关于Unicode转换代码的问题

Question

我是昨天才开始看的delphi，所以问题可能很初级，请见谅是《精通delphi7.0》上的例子程序书中在单元处定义类型，用于处理Unicode字串，
但是我不知道应该怎么放
代码如下：    
TCodePage = (cpThai,
               cpJapan,
               cpChineseSimplified,
               cpKorean,
               cpChineseTraditional,
               cpUnicode,
               cpEastEuropean,
               cpCyrillic,
               cpANSI,
               cpGreek,
               cpTurkish,
               cpHebrew,
               cpArabic,
               cpBaltic,
               cpKoreanJohab);
const CodePageIdentifiers:array[cpThai..cpKoreanJohab] of word
=(874,  //Thai
  932,
  936,
  949,
  950,
  1200,
  1250,
  1251,
  1252,
  1253,
  1254,
  1255,
  1256,
  1257,
  1361
  );
另外附上我打的。pas文件代码（各位如果有时间可以给我看一下不？不胜感激）
unit ChartoUnicode1;interfaceuses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls;type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    Edit3: TEdit;
    Button1: TButton;
    Button2: TButton;
    Button3: TButton;    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure FormClick(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }end;
var
  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);
var s: string;
i,j,k: integer;
a: array[1..1000] of Char;
begin
s:='';
for i:=1 to Length(Edit1.Text) do begin
j:=Integer (Edit1.Text[i]);
s:=s+Copy(Format('%X',[j+$100]),2,3);
end;Edit2.Text:=s;
StringToWideChar(Edit1.Text,@(a[1]),500);
s:='';
i:=1;
while((a[i]<>#0) or (a[i+1]<>#0)) do begin
j:=Integer(a[i]);
k:=Integer(a[i+1]);
s:=s+Copy(Format('%X',[j*$100+k+$10000]),2,5);
i:=i+2;
end;
Edit3.Text:=s;
end;procedure TForm1.Button2Click(Sender: TObject);
var
ptmp:PWideChar;
wlen:word;
begin
ptmp:=nil;
wlen:=2*Length(Edit1.Text)+2;
ReallocMen(ptmp,wlen);
ZeroMemory(ptmp,wlen);
MultiByteToWideChar(CodePageIdentifiers[cpChineseSimplified],
                    0,
                    PChar(Edit1.Text),
                    Length(Edit1.Text),
                    ptmp,
                    wlen
                    );
Canvas.Font.Color:=clBtnHighlight;
TextOutw(Canvas.Handle,200,200,ptmp,LStrLenW(ptmp));
Canvas.Font.Color:=clBtnShadow;
if ptmp<>nil then begin
FreeMem(ptmp);
ptmp:=nil;
end;
end;
procedure TForm1.Button3Click(Sender: TObject);
var
ptmp:PWidechar;
wlen:word;
begin
ptmp:=nil;
wlen:=2*Length(Edit1.Text)+2;
reallocMem(ptmp,wlen);
ZeroMemory(ptmp,wlen);
StringToWidechar(Edit1.Text,ptmp,wlen);
TextOutW(Canvas.Handle,200,200,ptmp,LStrLenW(ptmp));
Canvas.Font.Color:=clBtnShadow;
Caption:=wideCharToString(ptmp);
if ptmp<>nil then begin
FreeMem(ptmp);
ptmp:=nil;
end;
end;
end.

Answer 1

unit ChartoUnicode1; interface uses 
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, 
  Dialogs, StdCtrls; type 
//放这吧
{
TCodePage = (cpThai, 
              cpJapan, 
              cpChineseSimplified, 
              cpKorean, 
              cpChineseTraditional, 
              cpUnicode, 
              cpEastEuropean, 
              cpCyrillic, 
              cpANSI, 
              cpGreek, 
              cpTurkish, 
              cpHebrew, 
              cpArabic, 
              cpBaltic, 
              cpKoreanJohab); }
  TForm1 = class(TForm) 
    Label1: TLabel; 
    Label2: TLabel; 
    Label3: TLabel; 
    Edit1: TEdit; 
    Edit2: TEdit; 
    Edit3: TEdit; 
    Button1: TButton; 
    Button2: TButton; 
    Button3: TButton; 
    procedure Button1Click(Sender: TObject); 
    procedure Button2Click(Sender: TObject); 
    procedure Button3Click(Sender: TObject); 
    procedure FormClick(Sender: TObject); 
  private 
    { Private declarations } 
  public 
    { Public declarations } end; 
//
{
const CodePageIdentifiers:array[cpThai..cpKoreanJohab] of word 
=(874,  //Thai 
  932, 
  936, 
  949, 
  950, 
  1200, 
  1250, 
  1251, 
  1252, 
  1253, 
  1254, 
  1255, 
  1256, 
  1257, 
  1361 
  );
}
var 
  Form1: TForm1; 
可能是这样放的，嘎嘎

Answer 2

自己定义的，需要整个文件使用的一般都定义在
interface 
uses 
//使用单元
type
// 定义内容
end; 如果只是某个过程 或函数使用的就直接在
function /procedure  .... ;
type
// 定义内容
end; 
var
//定义变量
begin
 // 函数、过程体 
end;