Brolly with a sharp point on the end! Dual purpose weapon.
I think it might work, but would have the opposition in fits maybe!
I do recall reading one or two accounts by western observers who remarked how "effeminate" it seemed to them that Chinese soldiers carried umbrellas. I don't know though, considering how humid and hot it gets in parts of China, an umbrella doesn't seem like the worst piece of kit to me.
And yes, I guess if you had one with a strong shaft you could turn it around for some fancy hand-to-hand combat
By the way, I went back and checked my sources on the Japanese weather covers. According to one source, one of the other uses those covers were intended for was to obscure the glow of the lit match during night fighting.