Can private keys be exported more than once in Electrum client so long as the've not been spent? Assuming one exported the private keys from one's offline Electrum wallet to a CSV file (also offline), they obviously have not been 'spent'. The whole thing was done offline. My question is this: if I were now to go online and try to spend the bitcoins covered by those private keys, are the bitcoins still there? Or does the exportation of the private keys to the CSV file equal the spending of those coins so far as the Electrum client is concerned? To put it another way, can the private keys be exported more than once so long as they have not been spent? I'm hope I'm explaining myself clearly.

[I recently made my first Bitcoin purchase and I did so into an Electrum wallet, which I am currently keeping on an offline computer. I could not see my private keys anywhere and was unsure that I'd received them and so I exported them to the CSV file purely to ascertain that I had, in fact, received them. (I would not do so on any future purchases, now that I'm confident that the private keys would be there to be generated from the seed since they are plainly more secure unexported from an encrypted wallet than on a CSV file, but, hey, my first time and no evidence or explanation that I indeed had received them ...] - Terrylei
It seems like you don't understand how Bitcoins, private keys and bitcoin addresses work, so I'll make it simple:

As I explained to you here https://bitcoin.stackexchange.com/a/11479/2467 , you should not (more like MUST NOT) export your private keys from an Electrum seed. This can compromise all your private keys.

Your private keys are derived from your seed every time you make a payment to sign the transaction. So there's no need to see them, the client calculate them for you, use them, and hide them again. all you need is to keep your seed safe.

If you want to know the balance in your offline Electrum wallet's addresses you can use a seedless wallet on an online computer. To do that look for your Master Public Key in the offline Electrum, and restore from your MPK on an online computer.

You don't need your private keys to know the balance on their public addresses anyway. Public addresses are public and if you have already received on them, you can check their balance on Blockchain.info