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Clipboard backup

Hi there,
How can I make a copy of the content of the clipboard in the memory? And how to restore the clipboard from the copy?

Thanks in advance.

PS. The content of the clipboard can be anything, not necessarily text

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edey

Some of this stuff can be simplified using the TClipboard object (don't instantiate it, just add clipbrd to your uses clause). The help files have these example for getting & setting data from/to the clipboard (also most vcl's have a methods to do this)

var

MyHandle: THandle;
TextPtr: PChar;
MyString: string;
begin
ClipBoard.Open;
try
MyHandle := Clipboard.GetAsHandle(CF_TEXT);
TextPtr := GlobalLock(MyHandle);
MyString := StrPas(TextPtr);
GlobalUnlock(MyHandle);
finally
Clipboard.Close;
end;
end;

procedure TForm1.Button1Click(Sender: TObject);
var
MyFormat : Word;
Bitmap : TBitMap;
AData,APalette : THandle;
begin
Bitmap := TBitmap.Create;
try
Bitmap.LoadFromFile('c:\Program Files\Common Files\Borland Shared\Images\Splash\256color\factory.bmp');
Bitmap.SaveToClipBoardFormat(MyFormat,AData,APalette);
ClipBoard.SetAsHandle(MyFormat,AData);
finally
Bitmap.Free;
end;
end;

If, OTOH, you've got this stuff down & just need to know when to get the data (as there are no events for TClipboard) you would then need to register a clipBoardViewer:

unit Unit1;

interface

uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, clipbrd;

type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
{ Private declarations }
nextViewer : HWND;
procedure doWMDRAWCLIPBOARD(var msg : TWMDRAWCLIPBOARD);message WM_DRAWCLIPBOARD;
procedure doWMCHANGECBCHAIN(var msg : TWMCHANGECBCHAIN);message WM_CHANGECBCHAIN;
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.FormCreate(Sender: TObject);
begin
nextViewer := setClipBoardViewer(handle);
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
changeClipBoardChain(handle,nextViewer);
end;

procedure TForm1.doWMCHANGECBCHAIN(var msg : TWMCHANGECBCHAIN);
begin
if msg.remove = nextViewer then
nextViewer := msg.Next
else
sendMessage(nextViewer,WM_CHANGECBCHAIN,msg.remove,msg.next);
end;

procedure TForm1.doWMDRAWCLIPBOARD(var msg : TWMDRAWCLIPBOARD);
begin
//this proc will get called anytime anything get's added
//to the clipboard. From here you can query the cb as to
//current formats & data & such, as seen above
end;

end.

GL
Mike

yingkit

ASKER

Thank you all.