Are all vampires evil

No. Not all vampires are evil. Some are good beyond imagining, though for them to get to this point, some amount of control is needed. An example of good vampires are the Cullens from Twilight, the vampyres from the House of Night series, and the Moroi and dhampirs from the Vampire Academy series. And while there isa formidable amount of good vamps, they will most always be outnumbered by the bad vamps.