Yes. I've had to help repair aircraft post lightning strike. You can tell when it has because it will have two small burn marks/holes on the airframe, an entry and exit point. When it lands, the avionics, electrical systems and the flying controls have to be fully checked for faults. Fuses have to be checked and the panels that took the brunt of the strike have to be repaired/replaced. Aircraft (especially airliners) are safe from the strikes as the lightning tends to go around the external airframe of the aircraft, so passengers won't notice the effect. It's not unsafe for the people on board, but the avionics may have problems until it is investigated and repaired. The aircraft usually doesn't fly for 1-2 weeks after the incident while groundcrew fix it.
Don't worry about it though. It's not as bad as it seems.
More modern aircraft are totally shielded from the effects, so no damage is taken.
Oh, and the guy who said that the aircraft has nothing magnetic in it was talking complete crap. When you pass an electrical current through a wire, you produce a magnetic field. When the system power is on, magnetic fields are present.
5 1/2 years in the RAF as an Avionics technician