创建一个可调整大小和拖拽的Edit

 //---------------------------------------------------------------------------
__fastcall tform1::tform1(tcomponent* owner)
    : tform(owner)

{

    //修改此单字符串窗口组件性质，可自由缩放大小

    dword dwstyle = ::getwindowlong(edit1->handle, gwl_style);

    ::setwindowlong(edit1->handle, gwl_style, dwstyle | ws_sizebox);

    //修正此单字符串窗口组件在form1上的实际尺寸与范围

    //以便user直接调整单字符串窗口组件边沿

    ::movewindow(edit1->handle, edit1->left, edit1->top,
             edit1->width, edit1->height + 1, true);

}

//---------------------------------------------------------------------------

//当鼠标保持箭头图标时，edit1即可被拖曳

void __fastcall tform1::edit1mousedown(tobject *sender,
      tmousebutton button, tshiftstate shift, int x, int y)

{

    if(edit1->cursor == crarrow )

    {

        //释放原有鼠标捕捉状态，

        //并同时送出鼠标单击位置等同于窗口标题栏可拖曳窗口的属性

        ::releasecapture();

        sndmsg(edit1->handle, wm_nclbuttondown, htcaption, 0);

  }

}

//---------------------------------------------------------------------------

void __fastcall tform1::edit1mousemove(tobject *sender, tshiftstate shift,
      int x, int y)

{

    //鼠标在edit1上移动时，仍保持箭头图标

    edit1->cursor = crarrow;

}

//---------------------------------------------------------------------------