Key Hook的键盘扫描代码

来自：jbas, 时间：2002-1-24 15:42:00, ID：882324 [显示：小字体 | 大字体]
这是一个hook程序的一部分！我想知道下面的EvnMsg.paramL=20520这个“20520"怎样的到的
，如果我想监视a,b,1,2这样的数，那个evnmsg.paraml=???;哪有介绍呀。delphi找不到那个20520的定义
谢谢！
function rPro(iCode:integer;wParam:wParam;lParam:lParam):LResult;stdcall;
var EvnMsg:TEventMsg;
begin
EvnMsg:=PEventMsg(lParam)^;
if EvnMsg.message=WM_KEYDOWN then
begin
if EvnMsg.paramL=20520 then //‘↓’键被按下
showmessage('↓');
end;
end;
　
来自：zhangkan, 时间：2002-1-24 16:50:00, ID：882547
找到的一点,但因为周围没有相关的书和资料,不能给你好的解释.呵呵,这会儿也没时间.
不过,你可以参考这些键值了.出自jingtao.
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
StdCtrls, ExtCtrls;
type
TForm1 = class(TForm)
ListBox1: TListBox;
Button1: TButton;
Button2: TButton;
procedure FormCreate(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
private
function Keyhookresult(lP: integer; wP: integer): pchar;
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
hookkey: string;
hooktimes: word;
hHook: integer;
implementation
{$R *.DFM}
function TForm1.Keyhookresult(lP: integer; wP: integer): pchar;
begin
result := '[Print Screen]';
case lp of
10688: result := '`';
561: Result := '1';
818: result := '2';
1075: result := '3';
1332: result := '4';
1589: result := '5';
1846: result := '6';
2103: result := '7';
2360: result := '8';
2617: result := '9';
2864: result := '0';
3261: result := '-';
3515: result := '=';
4177: result := 'Q';
4439: result := 'W';
4677: result := 'E';
4946: result := 'R';
5204: result := 'T';
5465: result := 'Y';
5717: result := 'U';
5961: result := 'I';
6223: result := 'O';
6480: result := 'P';
6875: result := '[';
7133: result := ']';
11228: result := ';
7745: result := 'A';
8019: result := 'S';
8260: result := 'D';
8518: result := 'F';
8775: result := 'G';
9032: result := 'H';
9290: result := 'J';
9547: result := 'K';
9804: result := 'L';
10170: result := ';';
10462: result := '''';
11354: result := 'Z';
11608: result := 'X';
11843: result := 'C';
12118: result := 'V';
12354: result := 'B';
12622: result := 'N';
12877: result := 'M';
13244: result := ',';
13502: result := '.';
13759: result := '/';
13840: result := '[Right-Shift]';
14624: result := '[Space]';
283: result := '[Esc]';
15216: result := '[F1]';
15473: result := '[F2]';
15730: result := '[F3]';
15987: result := '[F4]';
16244: result := '[F5]';
16501: result := '[F6]';
16758: result := '[F7]';
17015: result := '[F8]';
17272: result := '[F9]';
17529: result := '[F10]';
22394: result := '[F11]';
22651: result := '[F12]';
10768: Result := '[Left-Shift]';
14868: result := '[CapsLock]';
3592: result := '[Backspace]';
3849: result := '[Tab]';
7441:
if wp > 30000 then
result := '[Right-Ctrl]'
else
result := '[Left-Ctrl]';
13679: result := '[Num /]';
17808: result := '[NumLock]';
300: result := '[Print Screen]';
18065: result := '[Scroll Lock]';
17683: result := '[Pause]';
21088: result := '[Num0]';
21358: result := '[Num.]';
20321: result := '[Num1]';
20578: result := '[Num2]';
20835: result := '[Num3]';
19300: result := '[Num4]';
19557: result := '[Num5]';
19814: result := '[Num6]';
18279: result := '[Num7]';
18536: result := '[Num8]';
18793: result := '[Num9]';
19468: result := '[*5*]';
14186: result := '[Num *]';
19053: result := '[Num -]';
20075: result := '[Num +]';
21037: result := '[Insert]';
21294: result := '[Delete]';
18212: result := '[Home]';
20259: result := '[End]';
18721: result := '[PageUp]';
20770: result := '[PageDown]';
18470: result := '[UP]';
20520: result := '[DOWN]';
19237: result := '