Mega Code Archive
Hook into the Clipboard Notification Chain
<![CDATA[
Title: hook into the Clipboard Notification Chain?
{
*Just create a new form and call it ClipFormats.
*Drop a TButton and call it btnUpdate.
*Drop a TListBox and call it lbFormats.
Then just add the code below and hook up all the event handlers.
All it does is display all the formats currently on the clipboard and
updates as soon as the clipboard changes.
* Erstelle eine Neue Form und nenne sie ClipFormats.
* Plaziere einen TButton auf ihr und nenne ihn btnUpdate.
* Plaziere eine TListBox auf ihr und nenne sie lbFormats.
Dann füge den untenstehenden Code hinzu und linke alle Ereignis-Prozedure.
Es zeigt dann alle Formate an, welche sich momentan in der Zwischenablage
befinden und wird aktualisiert, sobald sich der Inhalt der Zwischenablage ändert.
}
unit DynaClip;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;
type
TClipFormats = class(TForm)
btnUpdate: TButton;
lbFormats: TListBox;
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
procedure btnUpdateClick(Sender: TObject);
private
{ Private declarations }
NextWindow: HWND;
procedure WMChangeCBChain(var Message: TWMChangeCBChain); message
WM_CHANGECBCHAIN;
procedure WMDrawClipboard(var Message: TWMDrawClipboard); message
WM_DRAWCLIPBOARD;
public
{ Public declarations }
end;
var
ClipFormats: TClipFormats;
implementation
{$R *.DFM}
procedure TMDIChildClipFormats.FormCreate(Sender: TObject);
begin
NextWindow := SetClipboardViewer(Handle);
end;
procedure TClipFormats.FormDestroy(Sender: TObject);
begin
ChangeClipboardChain(Handle, NextWindow);
end;
procedure TClipFormats.WMChangeCBChain(var Message: TWMChangeCBChain);
begin
with Message do
begin
if (Remove = NextWindow) then
begin
NextWindow := Next;
end
else
begin
SendMessage(NextWindow, WM_CHANGECBCHAIN, Remove, Next);
end;
end;
end;
procedure TClipFormats.WMDrawClipboard(var Message: TWMDrawClipboard);
begin
btnUpdate.Click;
SendMessage(NextWindow, WM_DRAWCLIPBOARD, 0, 0);
end;
procedure TClipFormats.btnUpdateClick(Sender: TObject);
const
PreDefinedFormats: array[1..16] of string = ('CF_TEXT',
'CF_BITMAP',
'CF_METAFILEPICT',
'CF_SYLK',
'CF_DIF',
'CF_TIFF',
'CF_OEMTEXT',
'CF_DIB',
'CF_PALETTE',
'CF_PENDATA',
'CF_RIFF',
'CF_WAVE',
'CF_UNICODETEXT',
'CF_ENHMETAFILE',
'CF_HDROP',
'CF_LOCALE');
var
ClipFormat: TClipFormat;
szBuffer: array[0..511] of Char;
FormatID: string;
begin
if not OpenClipboard(Handle) then Exit;
try
lbFormats.Items.BeginUpdate;
try
lbFormats.Items.Clear;
ClipFormat := EnumClipboardFormats(0);
while (ClipFormat 0) do
begin
if (ClipFormat in [1..16]) then
begin
FormatID := PreDefinedFormats[ClipFormat];
end
else
begin
GetClipboardFormatName(ClipFormat, szBuffer, SizeOf(szBuffer));
FormatID := string(szBuffer);
end;
lbFormats.Items.Add(Format('%s [%d]', [FormatID, ClipFormat]));
ClipFormat := EnumClipboardFormats(ClipFormat);
end;
finally
lbFormats.Items.EndUpdate;
end;
finally
CloseClipboard;
end;
end;
end.
]]>