WinAPI字符及字符串函數(shù)(2):CharLowerBuff-把緩沖區(qū)中指定數(shù)目的字符轉(zhuǎn)小寫

interface
    uses
    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}
    {對字符數(shù)組, 全部轉(zhuǎn)換}
    procedure TForm1.Button1Click(Sender: TObject);
    var
    buf: array[0..6] of Char;
    begin
    buf := 'ABCDEFG';
    CharLowerBuff(buf, Length(buf));
    ShowMessage(buf); {abcdefg}
    end;
    {只轉(zhuǎn)換前 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;
    {對字符串}
    procedure TForm1.Button4Click(Sender: TObject);
    var
    str: string;
    begin
    str := 'ABCDEFG';
    CharLowerBuff(@str[1], Length(str));
    ShowMessage(str); {abcdefg}
    end;