_buff = self.ch.recv(nbyte)
print (chardet.detect(_buff))
try:
_buff = _buff.decode(encoding='UTF-8', errors='strict')
except UnicodeDecodeError:
_buff = _buff.decode(encoding='gb2312', errors='strict')
cahrdet有置信度的,换句话说,它也不是百分百自信检查出来的一定正确