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Как послать данные другому приложению используя Auto Drag & Drop?

01.01.2007
uses
  ShellAPI;
 
function MakeDrop(const FileNames: array of string): THandle;
// Creates a hDrop Object
var
  I, Size: Integer;
  Data: PDragInfoA;
  P: PChar;
begin
  // Calculate memory size needed
  Size := SizeOf(TDragInfoA) + 1;
  for I := 0 to High(FileNames) do
    Inc(Size, Length(FileNames[I]) + 1);
  // allocate the memory
  Result := GlobalAlloc(GHND or GMEM_SHARE, Size);
  if Result <> 0 then
  begin
    Data := GlobalLock(Result);
    if Data <> nil then
      try
        // fill up with data
        Data.uSize := SizeOf(TDragInfoA);
        P  := PChar(@Data.grfKeyState) + 4;
        Data.lpFileList := P;
        // filenames at the at of the header (separated with #0)
        for I := 0 to High(FileNames) do
        begin
          Size := Length(FileNames[I]);
          Move(Pointer(FileNames[I])^, P^, Size);
          Inc(P, Size + 1);
        end;
      finally
        GlobalUnlock(Result);
      end
    else
    begin
      GlobalFree(Result);
      Result := 0;
    end;
  end;
end;
 
function MyEnum(Wnd: hWnd; Res: PInteger): Bool; stdcall;
// search for a edit control with classname 'TEditControl'
var
  N: string;
begin
  SetLength(N, MAX_PATH);
  SetLength(N, GetClassName(Wnd, Pointer(N), Length(N)));
  Result := AnsiCompareText('TEditControl', N) <> 0;
  if not Result then Res^ := Wnd;
end;
 
// Example: Open msdos.sys in Delphi's Editor window
procedure TForm1.Button1Click(Sender: TObject);
var
  Wnd: HWnd;
  Drop: hDrop;
begin
  // search for Delphi's Editor
  EnumChildWindows(FindWindow('TEditWindow', nil), @MyEnum, Integer(@Wnd));
  if IsWindow(Wnd) then
  begin
    // Delphi's Editor found. Open msdos.sys
    Drop := MakeDrop(['c:\msdos.sys']);
    if Drop <> 0 then PostMessage(Wnd, wm_DropFiles, Drop, 0);
    // Free the memory?
    GlobalFree(Drop);
  end;
end;

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