I cannot tell you the exact official position (or the N official positions as the case may be) but I can give you some useful personal anecdotal input.

Short: You are extremely unlikely to have any problems at all if you are otherwise sensibly behaved. If you did happen to incur the wrath of the authorities I would not be overly surprised if a statute relating to knife carrying was found to have been breached. It's not something I'd be concerned about personally, see below. YMMV. 

Long:

When I travel overseas on business I often carry one or two pocket knives along with a significant collection of electrical and mechanical tools. When I travel privately the tool collection reduces 'somewhat' but the knives remain. I used to carry a Swiss Army knife but find that an ordinary knife is overall more useful as an "engineering" tool in all sorts of situations. If I really want a screwdriver I usually have one with me. (Or two or three or six :-) ).

The following three paragraphs may seem unnecessary but are relevant to what follows:  

 - My knives are absolutely NOT intended as weapons. When occasion arises I instruct young people what to do with a knife if you are attacked - viz: "Bury it deep in your pocket and make sure nobody knows that you have it - odds are that any one who wishes you physical harm knows how to use a knife better than you do, will probably manage to take it from you and giving them something that may be more liable to kill you than what they have already is probably unwise." But - other people do not know why I carry them. 

 - The two knives I usually carry are metal, folding, single blade. About 3" I think. Neither is spring open but both can be seen as borderline 'flick knife' as both are designed to be opened one handed either by a stud on the blade on one which allows the thumb to swing the blade or by pressure on a short behind the hinge blade extension on the other which allows thumb pressure to rotate the blade. Both lock open and have a latch that must be operated to allow them to close. Again one handed with due practice. I practiced with both enough to allow me to withdraw the knife and open it in one motion and to also put it away one handed. 

 - ie the knives are of a type that while useful would be expected to be borderline legal or worse in some countries. They are sharp and pointed and made to be opened as they are taken from a pocket. The blades lock open.

I have travelled extensively in China - 15 visits and 6 months in China in the last 6 years. As well as travelling as a passenger in private cars I have travelled widely by train, taxi, bus and air. 

I bought both knives in China. One from a typical city-suburbs grocery store where it was on open display at a counter with maybe a dozen other models. The other from an inner city street market where it was on display with dozens of others among hundreds of sellers of which many would also have been selling knives.  

When I fly I check my pockets at check-in to ensure nothing unallowed is carried. I put one or two knives in the outer zipped pocket of my checked in bag and recover them on arrival.  They would show easily on XRay or the most causual inspection

The bags are on some occasions inspected and/or xrayed while out of my care. On one occasion I got my bag back last of anyone so that I was last in queue. It did not occur to me that this was not just happenstance :-). On arrival at security / customs I was invited to join half a dozen customs men in a side room and we spent a merry half hour or so looking at everything in all my bags and having me explain what each was.  I had a full electronics workshop with me :-). That was during the Olympics at Qingdao (Olympic yachting) and they were 'cautious'. The knives were not treated any different from anything else. (This was an internal non-border airport but these can be treated in much the same way as an international border.)

I have used the knives 'as required' in my China travels. Bag or shoe repair. Various misc tasks. 

In Urumqi (far North West China) the Uighur men all carry (I'm told) special curved and decorated knives. These are sold in all shapes and sizes in the shops and I saw groups of men sitting in circles inspecting knives - what they look for in them I did not find out.

I once - stupidly - failed to place a Swiss Army knife and it was found in my bag at boarding security at an inland (non-border) airport 


More soon.....