# 使用泛型的 TArray 从动态数组中查找指定元素

unit Unit1;

interface

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

type
TForm1 = class(TForm)
Button1: TButton;
Button2: TButton;
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
end;

var
Form1: TForm1;

implementation

{\$R *.dfm}

uses Generics.Collections; {引用泛型单元}

{从字符串数组中查找}
procedure TForm1.Button1Click(Sender: TObject);
var
arr: array of string;
num: Integer;
begin
{构建动态数组}
SetLength(arr, 5);
arr[0] := 'aaa';
arr[1] := 'bbb';
arr[2] := 'ccc';
arr[3] := 'ddd';
arr[4] := 'eee';

{查找}
TArray.BinarySearch<string>(arr, 'ddd', num);

{显示查找结果}
if num < Length(arr) then {如果 num = Length(arr) 就是没找到}
ShowMessage(IntToStr(num)); {3}
end;

{从整数数组中查找}
procedure TForm1.Button2Click(Sender: TObject);
var
arr: array of Integer;
num: Integer;
begin
{构建动态数组}
SetLength(arr, 5);
arr[0] := 11;
arr[1] := 22;
arr[2] := 33;
arr[3] := 44;
arr[4] := 55;

{查找}
TArray.BinarySearch<Integer>(arr, 44, num);

{显示查找结果}
if num < Length(arr) then {如果 num = Length(arr) 就是没找到}
ShowMessage(IntToStr(num)); {3}
end;

end.


posted on 2009-10-09 22:26  万一  阅读(...)  评论(...编辑  收藏