c – 按名称创建Protobuf消息对象

https://developers.google.com/protocol-buffers/docs/reference/cpp/google.protobuf.descriptor#DescriptorPool.generated_pool.details

所以,你可以这样做：

google::protobuf::Descriptor* desc =
    google::protobuf::DescriptorPool::generated_pool()
        ->FindmessageTypeByName("mypkg.myType");
assert(desc != null);

该库还维护一个对象,该对象可用于构造任何编译类型的实例,给定其描述符：

https://developers.google.com/protocol-buffers/docs/reference/cpp/google.protobuf.message#MessageFactory.generated_factory.details

所以你要这样做：

google::protobuf::message* message =
    google::protobuf::messageFactory::generated_factory()
        ->GetPrototype(desc)->New();