unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
  mystr:string;//定義字符串
  strlength:integer;
begin
  setlength(mystr,5);//將字符串定義為5個(gè)字節(jié)的長度
  strlength:=length(mystr);//取得字符串長度
  showmessage(inttostr(strlength));//顯示字符串長度
end;

end.