把Button1放在Form1上, 在放一個Panel1, 來接收拖放Button1.    __fastcall TForm1::TForm1(TComponent* Owner)
  : TForm(Owner)
{
  // 把DragMode設為自動, 讓系統幫你處理Drag-Drop
  Button1->DragMode = dmAutomatic;
}    // 設定Panel1的 OnDragOver 事件
void __fastcall TForm1::Panel1DragOver(TObject *Sender, TObject *Source,
      int X, int Y, TDragState State, bool &Accept)
{
  AnsiString szBuf = Source->ClassName();
  // 取得拖放的Class Name, 檢查是否是Button
  if (szBuf == "TButton")
  {
    // 檢查是否是Button1, 如果是Button1才讓它可拖放(Accept = TRUE)
    if (((TButton*)Source)->Name == "Button1")
      Accept = TRUE;
  }
}    // 設定Panel1的 OnDragDrop 事件 
void __fastcall TForm1::Panel1DragDrop(TObject *Sender, TObject *Source,
      int X, int Y)
{
  AnsiString szBuf = Source->ClassName();
  if (szBuf == "TButton")
  {
    // 檢查是否是Button1, 如果是, 把Button1放到Panel1裡
    if (((TButton*)Source)->Name == "Button1")
    {
      ((TButton*)Source)->Parent = Panel1;
      ((TButton*)Source)->Left = X;
      ((TButton*)Source)->Top = Y;
    }
  }
}