unit Unit1;interfaceuses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls;type  TForm1 = class(TForm)    Button1: TButton;    Button2: TButton;    Button3: TButton;    Button4: TButton;    procedure Button1Click(Sender: TObject);    procedure Button2Click(Sender: TObject);    procedure Button3Click(Sender: TObject);    procedure Button4Click(Sender: TObject);  end;var  Form1: TForm1;implementation{$R *.dfm}{对字符数组, 全部转换}procedure TForm1.Button1Click(Sender: TObject);var  buf: array[0..6] of Char;begin  buf := 'ABCDEFG';  CharLowerBuff(buf, Length(buf));  ShowMessage(buf); {abcdefg}end;{只转换前 3}procedure TForm1.Button2Click(Sender: TObject);var  buf: array[0..6] of Char;begin  buf := 'ABCDEFG';  CharLowerBuff(buf, 3);  ShowMessage(buf); {abcDEFG}end;{返回值}procedure TForm1.Button3Click(Sender: TObject);var  buf: array[0..6] of Char;  num: Integer;begin  buf := 'ABCDEFG';  num := CharLowerBuff(buf, 4);  ShowMessageFmt('%s, %d', [string(buf), num]); {abcdEFG, 4}end;{对字符串}procedure TForm1.Button4Click(Sender: TObject);var  str: string;begin  str := 'ABCDEFG';  CharLowerBuff(@str[1], Length(str));  ShowMessage(str); {abcdefg}end;end.