子界

万一老师博客:http://www.cnblogs.com/del/archive/2007/11/30/978672.html

//定义
type
  Ten = 1..10;
  OverHundred = 100..1000;
  Uppercase = 'A'..'Z';
  //TMonth = Jan..Dec;

//应用
var
  UppLetter: UpperCase;
begin
  UppLetter := 'F';

//判断是否属于子界范围
var
  i: Integer;
begin
  i := 1;
  if i in [0..10] then
    ShowMessage('i 大于0、小于10');
end;

//根据枚举定义子界
type
  TColors = (Red,Blue,Green,Yellow,Orange,Purple,White,Black);
  TMyColors = Blue..Yellow;
var
  MyColor: TMyColors;
begin
  MyColor := Blue;
  ShowMessage(IntToStr(Ord(MyColor)));  //1
end;

//遍历子界
var
  character: 'a' .. 'z';
  s: string;
begin
  for character in [Low(character) .. High(character)] do
  begin
    s := s + character;
  end;
  ShowMessage(s);  //abcdefghijklmnopqrstuvwxyz
end;

原文地址:https://www.cnblogs.com/del88/p/6363029.html