National Semiconductor Corp's analog design guru Bob Pease suggests this for circuit boards and some other electronics. The boards can definitely survive, they make it through photoresist and etch without problem. But all the keys might trap water, so I'd want to turn the thing over several times to make sure it's really dry.
Several decades ago I had a telephone get soaked in a basement flood of murky water. Phone wasn't working due to mud shorting out the innards, so I opened it up, flushed it out with a garden hose, and baked it dry at 140 degrees F. Phone worked great. This was one of the old phones with dial and mechanical bell.