The one that nobody has thought about, use a little common sense, inform the man that he is not permitted to carry a knife of any kind within the court, place said object in an envelope, seal the envelope and have the man sign across the seal. Then give the man a receipt for the item and inform him that he can pick the item up when he departs.
I've been a bit harsh on ol' Grandpa Read.
The only time this has affected me it happened just as
leon-1 describes...
Several years ago I went to Wimbledon for the day with my brother - we were both early 20s but reasonably well turned-out - and my mum (bless her!) made us up a coolbox for lunch.
Included in the lunch were a few nectarines that were still slightly hard, so mum (unknown to us) packed a v. sharp paring knife with the sandwiches.
When security on the gate searched the bag they found the knife immediately - bear in mind the stabbing of Monica Seles on a tennis court was still in people's minds - so this was a big no-no.
But as
leon-1 suggests, they explained why we weren't allowed it (they could tell by our reaction that we were gobsmacked that Mum could be so daft!) and put it in a named envelope to collect later.
That strikes me as the perfect solution - although the political climate was different then - and we learned a useful lesson.
Having said that, knowing the level of assault that takes place in hospitals and court buildings etc I can see why they have a zero tolerance approach to knives.
But my experience at Wimbledon shows how it can - and perhaps
should - happen in reality.
Mr Read was unlucky - a year ago, or in another location, he probably would have been told he was a silly chap and to take more care next time. Unfortunately the current media-driven public hysteria over knife-crime means that this will happen more and more (although the fact it is "news" suggests it's not all that common).
So there you go... even self-righteous young whippersnappers can make the same mistakes as the older generation, and they* would no doubt whinge mightly if they received the same treatment
*by which, of course, I mean "me"