Delphi調用WinAPI 字符及字符串函數(1)

CharLower - 字符或字符串轉小寫

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;
　　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;
begin
　str := 'ABC';
　str := LowerCase(str);
　ShowMessage(str); {abc}
end;