british citizrlen in kenya

I am a British citizen currently in Nairobi. I require a Chinese visa, however don't have a resident permit. Is there any way I would be able to obtain it whilst in china, as I do not have time to obtain one once I am back in London.

for example would it be feasible for me to apply for it with the London office online,and then get my passport stamped here in Nairobi upon approval?

many thanks