// 获取网络环境的方法
+ (NSString *)networktype{
  NSArray *subviews = [[[[UIApplication sharedApplication] valueForKey:@"statusBar"] valueForKey:@"foregroundView"]subviews];
  NSNumber *dataNetworkItemView = nil;

  for (id subview in subviews) {
    if([subview isKindOfClass:[NSClassFromString(@"UIStatusBarDataNetworkItemView") class]]) {
      dataNetworkItemView = subview;
      break;
    }
  }

  switch ([[dataNetworkItemView valueForKey:@"dataNetworkType"]integerValue]) {
    case 0:
      return @"无服务";

    case 1:
      return @"2G";

    case 2:
      return @"3G";

    case 3:
      return @"4G";

    case 4:
      return @"LTE";

    case 5:
      return @"Wifi";


    default:
      break;
  }
  return @"";
}