无论在哪里调用serve，第二个参数似乎可以是各种各样的东西，包括'0.0.0.0'：https://pub.dev/documentation/dart_frog/latest/dart_frog/serve.html。向下搜索，我们最终找到的地址为：

/// The [address] can either be a [String] or an
  /// [InternetAddress]. If [address] is a [String], [bind] will
  /// perform a [InternetAddress.lookup] and use the first value in the
  /// list. To listen on the loopback adapter, which will allow only
  /// incoming connections from the local host, use the value
  /// [InternetAddress.loopbackIPv4] or
  /// [InternetAddress.loopbackIPv6]. To allow for incoming
  /// connection from the network use either one of the values
  /// [InternetAddress.anyIPv4] or [InternetAddress.anyIPv6] to
  /// bind to all interfaces or the IP address of a specific interface.

看起来你想要InternetAddress.anyIPv4作为你的值。