学步园

问题来源: http://www.cnblogs.com/del/archive/2008/05/11/978683.html#1191835

---

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs;

type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
var
  set1: set of Char; {定义一个字符集合变量}
  c: Char;           {定义个字符用于遍历集合}
  num: Integer;      {用于计数}
begin
  set1 := ['a'..'z', 'A'..'Z', '0'..'9']; {给集合赋值}
  
  num := 0;
  for c in set1 do Inc(num); {遍历字符集合 set1, 让 num 计数}   

  ShowMessage(IntToStr(num)); {62}
end;

end.