WinAPI字符及字符串函數(shù)(1):CharLower-字符或字符串轉(zhuǎn)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;
    Button5: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure Button5Click(Sender: TObject);
    end;
    var
    Form1: TForm1;
    implementation
    {$R *.dfm}
    {對字符}
    procedure TForm1.Button1Click(Sender: TObject);
    var
    C: Char;
    begin
    C := 'A';
    C := Char(CharLower(PChar(C)));
    ShowMessage(C); {a}
    end;
    {對字符常量}
    procedure TForm1.Button2Click(Sender: TObject);
    var
    C: Char;
    begin
    C := Char(CharLower(PChar('A')));
    ShowMessage(C); {a}
    end;
    {對字符數(shù)組}
    procedure TForm1.Button3Click(Sender: TObject);
    var
    Arr: array[0..2+1] of Char;
    begin
    Arr := 'ABC';
    CharLower(Arr);
    ShowMessage(Arr); {abc}
    end;
    {對字符串}
    procedure TForm1.Button4Click(Sender: TObject);
    var
    str: string;
    begin
    str := 'ABC';
    CharLower(@str[1]);
    ShowMessage(str); {abc}
    end;
    {Delphi 的 SysUtils.LowerCase}
    procedure TForm1.Button5Click(Sender: TObject);
    var
    str: string;
    beginstr := 'ABC';
    str := LowerCase(str);
    ShowMessage(str); {abc}
    end;