Delphi調用WinAPI 字符及字符串函數(2)

CharLowerBuff - 把緩沖區中指定數目的字符轉小寫

unit Unit1;

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}

{對字符數組, 全部轉換}

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;