WM_COPYDATA

Sender:

代码
unit SenderMain;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;

type

TCopyDataType
= (cdtString = 0, cdtImage = 1, cdtRecord = 2);

TSampleRecord
= packed record
s :
string[50];
i : integer;
d : TDateTime;
end;

TSenderMainForm
= class(TForm)
SendDataButton: TButton;
rgCopyOptions: TRadioGroup;
procedure SendDataButtonClick(Sender: TObject);
private
procedure SendData(copyDataStruct : TCopyDataStruct);

procedure SendString();
procedure SendImage();
procedure SendRecord();
public
{ Public declarations }
end;

var
SenderMainForm: TSenderMainForm;

implementation

{$R *.dfm}

procedure TSenderMainForm.SendData(
copyDataStruct: TCopyDataStruct);
var
receiverHandle : THandle;
res : integer;
begin
receiverHandle :
= FindWindow(PChar('TReceiverMainForm'),PChar('ReceiverMainForm'));
if receiverHandle = 0 then
begin
ShowMessage(
'CopyData Receiver NOT found!');
Exit;
end;

res :
= SendMessage(receiverHandle, WM_COPYDATA, Integer(Handle), Integer(@copyDataStruct));

if res > 0 then ShowMessage(Format('Receiver has %d lines in Memo!',[res]));
end;

procedure TSenderMainForm.SendDataButtonClick(Sender: TObject);
begin
if rgCopyOptions.ItemIndex = -1 then
begin
ShowMessage(
'Nothing selected!');
Exit;
end;

case rgCopyOptions.ItemIndex of
0 : SendString;
1 : SendImage;
2 : SendRecord;
end;
end;

procedure TSenderMainForm.SendImage();
var
ms : TMemoryStream;
bmp : TBitmap;
copyDataStruct : TCopyDataStruct;
begin
ms :
= TMemoryStream.Create;
try
bmp :
= self.GetFormImage;
try
bmp.SaveToStream(ms);
finally
bmp.FreeImage;
end;
copyDataStruct.dwData :
= Integer(cdtImage); //use it to identify the message contents
copyDataStruct.cbData :
= ms.Size;
copyDataStruct.lpData :
= ms.Memory;

SendData(copyDataStruct);
finally
ms.Free;
end;
end;

procedure TSenderMainForm.SendRecord();
var
sampleRecord : TSampleRecord;
copyDataStruct : TCopyDataStruct;
begin
sampleRecord.s :
= 'Hello Receiver';
sampleRecord.i :
= 1982;
sampleRecord.d :
= Now;

copyDataStruct.dwData :
= Integer(cdtRecord); //use it to identify the message contents
copyDataStruct.cbData :
= SizeOf(sampleRecord);
copyDataStruct.lpData :
= @sampleRecord;

SendData(copyDataStruct);

end;

procedure TSenderMainForm.SendString();
var
stringToSend :
string;
copyDataStruct : TCopyDataStruct;
begin
stringToSend :
= 'About Delphi Programming';

copyDataStruct.dwData :
= Integer(cdtString); //use it to identify the message contents
copyDataStruct.cbData :
= 1 + Length(stringToSend);
copyDataStruct.lpData :
= PChar(stringToSend);

SendData(copyDataStruct);
end;

end.
Receiver

代码
unit ReceiverMain;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls;

type
TCopyDataType
= (cdtString = 0, cdtImage = 1, cdtRecord = 2);

TSampleRecord
= packed record
s :
string[50];
i : integer;
d : TDateTime;
end;

TReceiverMainForm
= class(TForm)
cdMemo: TMemo;
receivedImage: TImage;
procedure FormCreate(Sender: TObject);
private
procedure WMCopyData(var Msg : TWMCopyData); message WM_COPYDATA;

procedure HandleCopyDataString(copyDataStruct : PCopyDataStruct);
procedure HandleCopyDataImage(copyDataStruct : PCopyDataStruct);
procedure HandleCopyDataRecord(copyDataStruct : PCopyDataStruct);
public
{ Public declarations }
end;

var
ReceiverMainForm: TReceiverMainForm;

implementation

{$R *.dfm}

{ TReceiverMainForm }

procedure TReceiverMainForm.FormCreate(Sender: TObject);
begin
cdMemo.Clear;
end;

procedure TReceiverMainForm.HandleCopyDataImage(
copyDataStruct: PCopyDataStruct);
var
ms: TMemoryStream;
begin
ms :
= TMemoryStream.Create;
try
ms.Write(copyDataStruct.lpData^, copyDataStruct.cbData);
ms.Position :
= 0;
receivedImage.Picture.Bitmap.LoadFromStream(ms);
finally
ms.Free;
end;

cdMemo.Lines.Add(Format(
'Received image at %s',[DateToStr(Now)]));
end;

procedure TReceiverMainForm.HandleCopyDataRecord(
copyDataStruct: PCopyDataStruct);
var
sampleRecord : TSampleRecord;
begin
sampleRecord.s :
= TSampleRecord(copyDataStruct.lpData^).s;
sampleRecord.i :
= TSampleRecord(copyDataStruct.lpData^).i;
sampleRecord.d :
= TSampleRecord(copyDataStruct.lpData^).d;

cdMemo.Lines.Add(Format(
'Received record at %s',[DateToStr(Now)]));
cdMemo.Lines.Add(Format(
'sampleRecord.s = %s',[sampleRecord.s]));
cdMemo.Lines.Add(Format(
'sampleRecord.i = %d',[sampleRecord.i]));
cdMemo.Lines.Add(Format(
'sampleRecord.d = %s',[DateToStr(sampleRecord.d)]));
end;

procedure TReceiverMainForm.HandleCopyDataString(
copyDataStruct: PCopyDataStruct);
var
s :
string;
begin
s :
= PChar(copyDataStruct.lpData);

cdMemo.Lines.Add(Format(
'Received string "%s" at %s',[s, DateToStr(Now)]));
end;


procedure TReceiverMainForm.WMCopyData(var Msg: TWMCopyData);
var
copyDataType : TCopyDataType;
begin
copyDataType :
= TCopyDataType(Msg.CopyDataStruct.dwData);

//Handle of the Sender
cdMemo.Lines.Add(Format(
'WM_CopyData from: %d',[msg.From]));

case copyDataType of
cdtString: HandleCopyDataString(Msg.CopyDataStruct);
cdtImage: HandleCopyDataImage(Msg.CopyDataStruct);
cdtRecord: HandleCopyDataRecord(Msg.CopyDataStruct);
end;

//Send something back
msg.Result :
= cdMemo.Lines.Count;
end;

end.

 

posted @ 2010-12-26 16:04  Jekhn  阅读(370)  评论(0编辑  收藏  举报