c# - PictureBox continues loading after closing the form -

i have form(images) called form(main). images form uses flow layout holds custom usercontrols. usercontrol has picturebox uses picturebox.loadasync() method image uri. problem network activity not stop after closing images form.

i have tried handling usercontrol.disposed event picturebox.cancelasync() on picturebox, no avail. should loading stops if images form has been closed.

try adding 'picturebox.cancelasync()' form's closed event handler. have no control of when disposed event fire.