集合
//定义
type
Uppercase =
'A'..'Z';
Letters =
set of Uppercase;
//基于子界定义
TBorderIcon = (biSystemMenu, biMinimize, biMaximize, biHelp);
TBorderIcons =
set of TBorderIcon;
//基于枚举定义
//应用
type
Uppercase =
'A'..'Z';
Letters =
set of Uppercase;
//基于子界定义
var
L1, L2, L3: Letters;
begin
L1 := [
'A',
'B',
'C'];
L2 := [
'K'];
L3 := [];
if 'A' in L1
then ShowMessage(
'true');
//true
if L2=[
'K']
then ShowMessage(
'true');
//true
if L3=[]
then ShowMessage(
'true');
//true
end;
//判断是否属于集合
type
TSet =
set of (A,B,C);
var
set1: TSet;
begin
set1 := [A,B];
if A
in set1
then
ShowMessage(
'集合 set1 包含 A');
end;
//集合元素的增减
type
TSet =
set of (A,B,C);
var
set1: TSet;
begin
set1 := [A];
set1 := set1 + [B];
//增加一个元素
Include(set1,B);
//增加一个元素
set1 := set1 - [B];
//排除一个元素
Exclude(set1,B);
//排除一个元素
end;
//集合添加元素举例
type
TCharSet =
set of char;
var
character:
'a'..'z';
charSet: TCharSet;
word:
string;
begin
charSet := [];
for character
in [Low(character) .. High(character)]
do
begin
if character
in [
'd',
'e',
'l',
'p',
'h',
'i']
then
begin
Include(charSet, character);
end;
end;
for character
in charSet
do
begin
word := word + character;
end;
ShowMessage(word);
//dehilp
end;
获取集合元素个数
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.
