For your reading pleasure, just some of the California knife laws:

California Penal Code

171.5.
(b) It is unlawful for any person to knowingly possess within any
sterile area of an airport, any of the items listed in subdivision
(c).
(c) The following items are unlawful to possess as provided in
subdivision (b):
(2) Any knife with a blade length in excess of four inches, the
blade of which is fixed, or is capable of being fixed, in an
unguarded position by the use of one or two hands

626.10. (a) Any person, except a duly appointed peace officer as defined in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2, a full-time paid peace officer of another state or the federal government who is carrying out official duties while in this state, a person summoned by any officer to assist in making arrests or preserving the peace while the person is actually engaged in assisting any officer, or a member of the military forces of this state or the United States who is engaged in the performance of his or her duties, who brings or possesses any dirk, dagger, ice pick, knife having a blade longer than 21/2 inches, folding knife with a blade that locks into place, a razor with an unguarded blade, a taser, or a stun gun, as defined in subdivision (a) of Section 244.5, any instrument that expels a metallic projectile such as a BB or a pellet, through the force of air pressure, CO2 pressure, or spring action, or any spot marker gun, upon the grounds of, or within, any public or private school providing instruction in kindergarten or any of grades 1 to 12, inclusive, is guilty of a public offense, punishable by imprisonment in a county jail not exceeding one year, or by imprisonment in the state prison

e) Subdivision (b) does not apply to any person who brings or possesses an ice pick or a knife having a fixed blade longer than 21/2 inches upon the grounds of, or within, any private university, state university, or community college for lawful use in or around a residence or residential facility located upon those grounds or for lawful use in food preparation or consumption

653k. Every person who possesses in the passenger's or driver's
area of any motor vehicle in any public place or place open to the
public, carries upon his or her person, and every person who sells,
offers for sale, exposes for sale, loans, transfers, or gives to any
other person a switchblade knife having a blade two or more inches in
length is guilty of a misdemeanor.
For the purposes of this section, "switchblade knife" means a
knife having the appearance of a pocketknife and includes a
spring-blade knife, snap-blade knife, gravity knife or any other
similar type knife, the blade or blades of which are two or more
inches in length and which can be released automatically by a flick
of a button, pressure on the handle, flip of the wrist or other
mechanical device, or is released by the weight of the blade or by
any type of mechanism whatsoever. "Switchblade knife" does not
include a knife that opens with one hand utilizing thumb pressure
applied solely to the blade of the knife or a thumb stud attached to
the blade, provided that the knife has a detent or other mechanism
that provides resistance that must be overcome in opening the blade,
or that biases the blade back toward its closed position.


12020. (a) Any person in this state who does any of the following
is punishable by imprisonment in a county jail not exceeding one year
or in the state prison:
(1) gives,lends, or possesses
any ballistic knife
any belt buckle knife
any lipstick case knife, any cane sword, any shobi-zue
any air gauge knife, any writing pen knife,
(4) Carries concealed upon his or her person any dirk or dagger
(8) As used in this section, a "ballistic knife" means a device
that propels a knifelike blade as a projectile by means of a coil
spring, elastic material, or compressed gas.
(13) As used in this section, a "belt buckle knife" is a knife
which is made an integral part of a belt buckle and consists of a
blade with a length of at least 21/2 inches.
(14) As used in this section, a "lipstick case knife" means a
knife enclosed within and made an integral part of a lipstick case.
(15) As used in this section, a "cane sword" means a cane, swagger
stick, stick, staff, rod, pole, umbrella, or similar device, having
concealed within it a blade that may be used as a sword or stiletto.
(16) As used in this section, a "shobi-zue" means a staff, crutch,
stick, rod, or pole concealing a knife or blade within it which may
be exposed by a flip of the wrist or by a mechanical action.
(18) As used in this section, an "air gauge knife" means a device
that appears to be an air gauge but has concealed within it a
pointed, metallic shaft that is designed to be a stabbing instrument
which is exposed by mechanical action or gravity which locks into
place when extended.
(19) As used in this section, a "writing pen knife" means a device
that appears to be a writing pen but has concealed within it a
pointed, metallic shaft that is designed to be a stabbing instrument
which is exposed by mechanical action or gravity which locks into
place when extended or the pointed, metallic shaft is exposed by the
removal of the cap or cover on the device.
(24) As used in this section, a "dirk" or "dagger" means a knife
or other instrument with or without a handguard that is capable of
ready use as a stabbing weapon that may inflict great bodily injury
or death. A nonlocking folding knife, a folding knife that is not
prohibited by Section 653k, or a pocketknife is capable of ready use
as a stabbing weapon that may inflict great bodily injury or death
only if the blade of the knife is exposed and locked into position.