NSURL请求中含有中文的解决方法
NSURL * nurl=[[NSURL alloc] initWithString:[urlString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
NSURL * nurl=[[NSURL alloc] initWithString:[urlString stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];